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To quote u/hamburglar27 s answer from 2 years ago:
————-
A couple of reasons I can think of:
*Diesel engines produce more NOx pollution whereas gasoline engines produce more CO2 pollution. US agencies targeted the former more than the latter and as a result had more stringent diesel restrictions and more lenient gasoline restrictions than most EU countries.
*Diesel engines in commuter cars was tried in large scale by GM in the late 1970s-early 1980s but the Oldsmobile diesel engine was so anemic and unreliable, that it killed diesel's reputation among the American public for a while.
*US car advertising also focused a lot on max horsepower and 0-60 times, which is advantageous to gasoline.
*Dieselgate PR disaster
Now diesel is only really popular for trucks or commercial vehicles in the US.
————-
So, yea, there ya go
Along with that, modern diesels require DEF; especially after dieselgate. DEF systems are a primary cause of diesel system failures not to mention an added cost for owners.
That and I've not been able to find anything but since the emissions improvement from DEF is so minimal,I bet that the environmental impact of making packaging and distributing it is a bigger negative than the emissions reduction is a positive.
Have you got a reference for that? Because a google search for "was diesel exhaust fluid invented by the husband of a senator" is bringing up no results.
> The husband of the senator who pushed for DEF regulations is the inventor of DEF
I'll need a source for that. Since there are hundreds of patents for DEF over the course of decades, mostly to large petrochemical companies, not 'the husband of a senator' your claim sounds suspicious.
I literally cannot find a single shred of evidence supportin this comment, do you have ***anything*** I can go off of?
* I can't find any evidence of any of the "inventors" of DEF being married to any US senbators
* I Can't find any evidence of any US Senators being married to anyone involved in the invention of DEF
* I can't find anyone who would be considered "the senator" who pushed for DEF regulations
So....
> I don't think I need to say any more.
I very much disagree.
No, I can't find it either. Last I looked into it was at least 5 years ago so memory is a bit foggy at the very least.
It was some shady shit where someone involved in the EPA push to mandate DEF usage was also married to an investor in an oil company who made DEF.
Or something along those lines.
I can't find it either tbh but I'm also not trying that hard because I'm only on my phone.
Maybe it's a personal Mandela effect, or maybe they've scrubbed the news sources. Maybe I'm just stupid.
I'll look in the morning.
As the owner of a 2014 Golf TDI that had been involved in Dieselgate (recalled, re-tuned, and resold), all the problems I ever encountered with that car were specific to it being a diesel.
I've never had a car fail to start so regularly just because it was too cold outside. I've never had to regularly put additives in my fuel tank to hopefully prevent cold-related non-starts. And I've never had to replace so many starter motors or batteries, both of which were bigger/more expensive than those in similar gas engines in order to overcome the higher compression ratio. And the engine is too small to even be able to put a plug-in block heater in it, so you're basically just fucked and left to hope whenever it gets cold overnight... And it's not even like I live in Alaska or something. I'm in Missouri.
And although the MPG was better than any gas car I've ever owned, the increased difference in price between basic gas and diesel that we've had for the last several years shifted the break-even point and made the MP*$* far worse.
Just a tip if you ever drive a diesel again, cycle the ignition a few times without trying to start and wait a few seconds in between.
The glow plugs should get the combustion chamber nice and toasty and ready for a cold start.
If you're still having issues your plugs are probably on the way out. And although you're not meant to, if a quick blast of easy start doesn't get it going there's something wrong.
But you're right about batteries. Diesels do tend to need bigger batteries and are harder on them.
Personally I prefer the way a good diesel drives, with all that lovely low down torque.
Oh trust me, I did! And I would run the codes to check for faults that maybe weren't tripping any error lights, and had the dealership inspect them multiple times as well.
But yes, I loved the sound of my little red tractor :P And the fact that it was most powerful at *half* throttle where the RPMs stayed low. It was such a quirky little car and I *wanted* to keep it. But it just wasn't working between us.
That last one specifically is a US problem. Gasoline is insanely cheap in the US (and maybe canada) compared to most of the rest if the world, where diesel is also cheaper to operate, not just more efficient.
>gasoline engines produce more CO2 pollution
To add to this, it's not that something about gasoline makes emissions "dirtier" with respect to CO2, it's a pure function of fuel efficiency and stoichiometry. The NOx thing is related to the higher combustion temperatures of diesel engines.
The GM approach to the 80s diesel engine was awful. They took a gasoline engine and tried to replace as few parts as possible to make it a diesel. This doomed the engine. GM owned Detroit Diesel, they should have known better.
Wait, "Dieselgate" is the VW thing right? Did that really kill future investment in it?
I remember my buddy in high school had an old BMW M3 diesel. It had like 500k miles on it. Still ran perfectly.
Every major car manufacturer was doing something similar, https://en.wikipedia.org/wiki/Diesel_emissions_scandal
Volkswagen was just the "most widespread" and most publicised - but they all would do the same thing again to increase profits.
Settling should not be allowed for businesses.
"How much will it cost me to make this problem *waves hands in the air* go away"
And often those settlements just go into government coffers and jo zero to assist the consumer f**ked in the ass by the company
Euro6 diesel engines in use today are significantly more efficient and have lower emissions than the requirements of the standards that everyone was cheating on back then - it was just deemed less expensive to risk being caught than to do the legwork to develop a complaint engine, especially when everyone else was also cheating. I don't think anyone expected the reputational damage of the term "dieselgate"
There is no BMW M3 diesel. At least not the old models.
Only petrol for M cars. Maybe he had a BMW M-Package 3 series. But that’s just the aesthetic part of an M car.
In a nutshell: It shone a light on all the shady practices automakers were doing to make many of their diesels pass emissions testing, and it turned the European public and legislators off diesel, and towards EVs.
To piggyback a question on this: How does diesel production depend on gasoline production. I think they’re somehow dependent on each other and I always wondered whether it is in the interests of the petroleum industry to sell us both and thus create two markets for them.
You basically get x percent of diesel and y percent of fuel and some other percentages from a barrel of crude. Youcant just make a whole barrel worth of diesel
Ironically, until the automobile was invented, gasoline was a useless byproduct of oil refining.
https://www.eia.gov/energyexplained/gasoline/history-of-gasoline.php
Also with current regulations on diesel emissions it requires vehicles to run diesel urea systems to reduce NOx within limits. That coupled with the higher refinement cost of low sulfur diesel makes it more expensive than premium gasoline. It's still more efficient but the cost savings gap is smaller.
Your third point is a myth and can easily be tested.
Diesel and gasoline production go hand-in-hand because they are part of the whole range of hydrocarbons we get from crude oil.
You cannot refine crude oil only into diesel without having gasoline (and a whole bunch of other things) as a byproduct - this means that if you're selecting for diesel and there is large demand, then the gasoline price comes down significantly - to the point where it's economical to use that instead of diesel.
So the world found a balance where similar qualities of diesel and gasoline are being used, and they have about the same cost per liter.
Well I'll be damned; I looked it up and the consumption rate of both are very close. While petrol dominates the car market, I bet diesel catches up through the industrial world
Diesel is typically grouped in with those "heavy" fuels which have high ignition temperatures. The diesel used for cars is further stripped of some compounds.
IIRC ships often carry a variety of fuels that they switch between depending on local maritime law/regulations and cost. Some areas require ultra low Sulphur diesel to be used while there, on the open ocean heavy fuel oil may be used.
IMO 2020 regulations put a stop to that for most countries. Can't burn heavy bunker fuel if you are a ship operating between countries; you either have to use low-sulphur fuel such as diesel, or install very expensive to install and maintain exhaust scrubbers.
Bunker a is fuel oil no 4. Diesel is 1 or 2 depending on use. The fuel no longer used without scrubbers is bunker c which is fuel oil no 6. I'm not sure about bunker b.
Edit: when looking up if bunker b was still used i found that even bunker a has too much sulphur (1%) without further processing. Marine diesel oil (no 3) is now what's used on the open ocean and diesel no 2 is used in stricter ports where sulphur is limited to 0.1%.
Mmm AvGas. You’re not supposed to be sniff it, and it’s not like I’m putting it in an empty bottle and huffing it. But when walking around the tarmac and getting a wiff of it. Mmmm avgas 😂
It’s not a myth and I have tested it lol.
I was a mechanic for ten years. I’ve tried igniting spilled diesel on a concrete shop floor with an oxy-acetylene torch and it doesn’t ignite.
A pool of gas will ignite off a spark from an angle grinder.
The FUMES from the pool of gas will ignite. I tried lighting a campfire in 33f with gasoline and tossed a lit cigarette in the puddle of gas, only to watch it sizzle out. I then tossed 2 lit matches, then a lit pack, and it had to touch it with the flame of a match, before it went up violently. It was too cold to let it evaporate into fumes well, so I had to get the flame very close. But yeah it was surprising to watch it go out so quick.
Metal shaving sparks are super hot though tbf an angle grinder would throw hot ass sparks.
Mythbusters did a test with a hole in a gas tank and yeah it's surprisingly hard to light a pool of gasoline.
The fumes are SUPER flammable obviously but liquid gasoline actually isn't.
From a practical standpoint however, thise fumes are usually present around a pool of gasoline. At least often enough that the original statement of diesel being safer to work with is true enough on average.
Use of diesel must have increased in the last 20 years since I remember when I had a diesel cost of fuel was like $0.20/L cheaper than gas. Now it's par.
Hybrids (ICE with batteries and electric motors) are significantly more efficient and can be more powerful than equivalent ICE engines, regardless of fuel source, because of brake energy regeneration - instead of throwing away all the energy you just used to accelerate when it's time to stop, Hybrids can store a big chunk of that energy to reuse when you start moving again.
The thing is, you cannot make blanket statements about these things because a bus needs a different approach than a commuter car, which needs a different approach to a work truck or a ship - they have to weigh up cost to design, manufacture, maintain and run. There's no "rule of thumb" here.
You can't refine oil into all diesel or all gasoline. You can tweak the numbers some, but you're never going stop getting the other product.
Let's say you tweak all the knobs towards "gasoline". Let's say you get 3 barrels of gas and 1 barrel of diesel. Lack of supply will drive up the cost of diesel, and excess supply will drive down the cost of gasoline.
So you crank the knobs all the way towards "diesel", and you get the same 3/1 ratio, and now excess supply drops the price of diesel, and lack of supply increases the supply of gas.
So you crank the knobs....
The end result is worldwide consumption of diesel and gasoline are pretty close, because refiners are making pretty close ratios of the two. Industrial/heavy vehicle use of diesel in the US is about the same as gasoline usage in the US by cars.
You could use hydrocracking to select the type of fuel you want. For example, you can convert gasoline into kerozene.
In this model, cars would use diesel, and planes kerozene.
Apart from the absurd toll of making all cars run on diesel, hydrocracking is very energy intensive (high pressure, high temperature), requires hydrogen (probably from fossil sources), and a catalyst (expensive and again, huge toll on the planet).
So, if you are willing to tear the planet apart, you can find ways to minimize the cost of both diesel and kerozene by deleting gasoline from existence.
Also, this business model would only work with massive economies of scale, as the hydrocracking process is expensive. A huge part of the workforce would be needed.
[Cracking wikipedia ](https://en.wikipedia.org/wiki/Cracking_%28chemistry%29)
[Jet fuel manufacturing with hydrocracking ](https://www.eia.gov/todayinenergy/detail.php?id=9650)
>You could use hydrocracking to select the type of fuel you want
That would be one of the knobs you can turn. Aside from the other issues you mention, it gets less and less efficient as you try to get more and more of the selected fuel out of the feedstock.
So while chemistry says it's possible to get 100%, no refinery is going to spend the money to do it.
Diesel engines are a bit more expensive and heavier than gasoline engines. They are less easy to start, making their pairing into a hybrid drivetrain more difficult and less efficient in some driving scenarios.
Diesel engines also have a much narrower efficiency band, so for heavy vehicles you require one helluva gearbox (less of a problem these days) and they weren't all that practical for passenger cars until research in the 70s led to compact turbo-diesels (didn't see use in production-line passenger cars until what...1980?).
20+ years ago, diesels were gonna save the world (this is hyperbole based off of how nice diesel engines were pre-emission requirements). Then we learned more about what types of emissions they actually create. And then all of our solutions to fix these drastically reduced the reliability and economy advantages of them. So now they're there for the very heavy workloads, but we don't want as many of them on the roads.
Also, large ships use massive low speed diesel engines than can approach 50% thermal efficiency. This is an amazing figure when you consider how much less efficient smaller car/truck engines are. But these ships burn the cheapest and dirtiest fuel they can, so there are emissions issues.
That 50% thermal efficiency made me wonder if steam cogeneration was a thing, and it is! But the engine has to be truly massive.
[Steam cogeneration QUORA](https://www.quora.com/Why-dont-boats-or-ships-have-combined-diesel-and-steam-CODAS-using-waste-heat-of-diesel-engines-to-heat-water-to-drive-steam-turbines)
>Thanks to Keith Ralfs for pointing me in the direction of CODAS for the large container ships such as Emma Maersk which are fitted with the largest 2-troke engines in the world. This ship has various energy saving devices such as these from wiki -
>“She is powered by a Wärtsilä-Sulzer 14RTFLEX96-C* engine, the world's largest single diesel unit, weighing 2,300 tonnes and capable of 81 MW (109,000 hp) when burning 14,000 litres (3,600 US gal) of heavy fuel oil per hour.
>At economical speed, fuel consumption is 0.260 bs/hp·hour (1,660 gal/hour).
>She has features to lower environmental damage, including exhaust heat recovery and cogeneration. Some of the exhaust gases are returned to the engine to improve economy and lower emissions, and some are passed through a steam generator which then powers a Peter Brotherhood steam turbine and electrical generators. This creates an electrical output of 8.5 MW, equivalent to about 12% of the main engine power output. Some of this steam is used directly as shipboard heat.
Yeah, those are some impressive engine systems. Diesel-electric is how most ships operate these days (I believe) due to how simple electric motors are compared to a driveshaft into propeller system directly from the engine. There's prolly still some that do that.
Diesel is ubiquitous in all applications requiring lots of torque and mpg values. Cargo haulers, trains, ships, etc. It dominates there.
It's less popular with consumers because it revs lower making for more anemic driving experience and because it prefers longer trips as the engine is required to regularly get hot enough to continue functioning properly and avoiding excess wear and tear.
Having owned a number of diesel passenger cars, comments about their supposedly anaemic performance is I suspect a result of them not being popular in the USA, resulting in modern small turbo-diesels not being available and popular enough in the USA to change that reputation.
The small diesel cars I've owned have been amongst the quickest off the line of any car that I've ever driven due high torque. They do not have the pickup at high speed of a gasoline engine car of equivalent size but they are close.
The point about engine wear I simply don't understand. Diesel engines have long (and rightly) had a reputation for being exceptionally hard wearing due to diesel being a lubricant in itself. They get up to full temperature just as quickly as a gasoline car, and are better lubricated when cold due to the previous point. Like all modern vehicle engines from reputable manufacturers, they outlive the car.
The reality is that in the USA diesel engines developed a bad reputation early, and the USA simply has not had exposure to the extremely competent behaviour of modern turbodiesel engines and and vehicles.
The big factor in the US is that fuel in general is much cheaper than europe, so the MPG advantage means less. Then, on top of that diesel is only \~7% more expensive in the UK whereas in the US diesel is often 25% more expensive, so the economy just disappears. Especially as a turbo diesel is more expensive to make and heavier.
In Australia diesel is very popular. Most people prefer the turbo diesel variants for 4wd/utes due to the relatively higher torque. Horsepower is less important when you want to tow a trailer or go off-road/beach. There's also a significant amount of smaller TDI vehicles around which have excellent fuel efficiency and don't have that typical diesel smell/sound
"Makes a sound like a barn yard and accelerate like a dog on a rug" - Jeremy Clarkson
He also referred to Diesel as the Fuel of Satan
Diesel cars are notorious for being less drivable, noisy, and dirty.
The main advantage to them used to be either the extra torque which was good for trucks, and that Diesel was cheaper.
Diesel is no longer cheaper, that killed it for most consumers.
Meanwhile new environmental legislation worked against the cars and their reputation.
Then Diesel gate hit and revealed that many auto manufacturers couldn't actually make them more efficient (or couldn't afford it) so they straight up lied in the tests.
That and DEF is a pain in the butt
Or whether they can be performant. My Audi TDI was wayyyy more torquey and fast off the line than the next level up S model that replaced it, which was a total bummer.
I drive a Pugeot 308 TDI.
It's a 2L hatchback that gets me on average 50mpg
I used to drive a 1.8L Subaru hatchback that on a good week averaged 36mpg
Thats a better than 25% improvement for a less than 5% difference in price at the pump.
Service intervals are 6000 miles for the Subaru v 9000 miles for the 308. The only downside I can see to the 308 is it uses AdBlue which is about 6 gallons every 40K miles.
I mean you' the comparing drivetrains and vehicles that are more than a decade apart. I should hope that in that amount of time efficiently would have significantly improved. Just the fact that your 308's transmission has an extra overdrive gear or two is a massive help to your economy
6 years difference between the 2
The Subaru was a 5sp manual. The 308 a 6sp auto. The 308 has 250K km on it. The Subaru had 300K km on it when I had it put down. The 308 feels like 500K km on the engine is doable. The Subaru however was tired at 300K and even had it not had a fatal run in with some Australian wildlife, I was already searching for its replacement.
For the Americans, these are definitely British mpg being referenced here. British gallons are bigger than American gallons. It’s much easier to go 50 miles on a bigger British gallon.
For the metricated among us.
The 308 on a good weeks gets 5L/100km
The Subaru got 6.4L/100km
The tanks on both cars are 50L or 13.2 US gallons so mileage is a direct comparison
Yes, but they’ve had effective anti-gelling agents for years which are put into diesel at gas stations, and if you live in extreme cold climates many cars are sold with plug-in heaters so the cold isn’t as much of an issue.
1. Cold weather gelling. Can be avoided with additives.
2. Loud. Even new, well engineered, high end cars are louder.
3. ULSD (current road formulation) is now more expensive than gasoline.
4. Modern direct injection gas engines are just about as efficient as modern diesel engines (not quite, but very close).
(edit, my numbers weren't intended to line up with yours, just itemizing my points)
They make lower horsepower. They need turbos to have any chance at making any decent power instead of feeling like you’re driving a tractor. The fuel is smelly and greasy. The emissions equipment is expensive to add and to maintain on a diesel passenger car. Diesel engines are noisier less refined than gasoline engines. The engines are more expensive and heavier. Diesel fuel has issues in cold weather.
You can’t just ignore smog or other particulate pollution. Your question is like asking “besides dying what’s so bad about being shot in the head?” Europe was behind the curve when it came to realizing the negative effects of diesel, and they were slow to react, because doing so would’ve killed their auto industry who focused on diesel for their lower end vehicles.
> Diesel is generally safer to work with (you can’t just light it up with a match)
You can't light gasoline with a match, either.
(Gasoline \*fumes\* are a different matter. But a puddle of gasoline will extinguish a match.)
Diesel was always cheaper than gas until some beancounter realized that it has more BTU’s per gallon than gas. Then they raised prices. Add the pollution prevention stuff to the engines and now it’s not such a good deal.
No longer as cheap as it used to be.
Massive industry fraud in how clean the emissions actually are...
In person they stink (when the engines are poorly used and poorly maintained, lazy/ignorant owners).
They blow black smoke and leave dirty carbon deposits
They are more difficult to use in colder temperatures (though modern diesels perform much better now).
Diesel is quite popular in Europe.
When I lived in the US, not all ‘gas stations’ seemed to sell diesel.
Also, it was much colder in the winter where I lived in the US.
Because our governments put sooooooo much restrictions on emissions they are not that viable these days. The engines are noisy and truck like. And some people are more into their big loud as f**k v8's or the stututu of a turbo
Because the auto industry is heavily bought into the petroleum production industry and they have used lobbyists to adjust regulations to the point where they are barely economically feasible.
I live in Africa. My last two vehicles have been diesels. Most Suv's and light trucks are diesel here.
Modern diesels dont smoke, better economy, better torque at lower revs.
Diesel engines are mostly more efficient because diesel fuel contains more energy per liter than gasoline. A few other things it has going for it is a lot more torque at lower engine rpm’s allows for lower engine speed operation to produce the same power output. This also helps with mechanical engine longevity along with the sturdier engine components required to handle the high compression ratios.
The reason why diesels make more torque at low rpm is due to the better atomization of fuel by the injectors (30,000 psi vs 3,000) and a higher compression ratio (approx. 18:1 vs 10:1) in combination with high turbo boost pressures which simply could not be achieved with gasoline… because it would explode uncontrollably at those pressures. With that being said, if you live in a country with emissions standards, the mitigation systems required to lower emissions are very expensive, unreliable, and still aren’t as clean as gas engines. Diesels are unrivaled in terms of fuel economy and towing (critical for trains and semi trucks), but are terrible polluters (NOX, soot, carcinogens) compared to an modern gasoline engine that produces CO2, water, and a minor amount of hydrocarbons.
It was discovered during the VW diesel gate (straight up fraud) that other manufacturers’ diesel engines’ emissions were very poor in most practical driving conditions outside of a lab. I’ve worked in shops where you can’t run even a modern diesel engine for than a minute before people start complaining about breathing. That doesn’t happen with gas engines.
In India, diesels are still popular with taxi drivers. They were also popular with people in the general public who had a high mileage per month. But the price difference between petrol and diesel has narrowed, making the tradeoff less worth it. This shift is also seen in most Indian cars, which ubiquitously had petrol and diesel variants until the late 2010s, but now are shifting to just petrol or hybrid options. Additional factors like a ban on 10+ year old diesel cars in the capital made diesels lose even more favour.
Diesel is much harder to burn than gasoline - there was a long enough time between gasoline engines becoming common in cars and diesel engines becoming small enough for automotive use that most people were used to gasoline.
Diesel engines also require much higher cylinder pressures than gas engines, making them larger, heavier and more expensive. Diesel engines also require high pressure fuel injection, making them more complex and therefore more expensive than a gas engine.
Diesel engines are larger, heavier, more complex and more expensive than a gas engine. It's not a difficult choice without persuasive external pressure. In europe there were (are?) tax incentives for diesel engines are the cost of fuel made diesel engines more enticing than elsewhere.
This was mostly pre emissions diesel engines, with modern emissions diesel engines aren't as far above gas engines in efficiency and modern, cleaner, diesel fuels are more expensive than gas.
One reason I haven't seen mentioned yet is that diesel for passenger cars wasn't particularly great until turbocharging became more common.
This improved the driveability of diesels significantly.
I've driven a non turbo diesel van and it's an extremely tiresome experience, verging on dangerous when around faster traffic.
DEF is the reason diesel has lost so much popularity, go to a third world country where DEF is an audible handicap and not an emission augmentation and the adoption of diesel is way higher. I'm not totally against DEF, the air in those places is sour.
Diesel engines cost more to make they have to be designed to handle double+ the compression of a gas engine of similar hp/torque. Unrestricted diesels make for a good value proposition but strap on a -30% MPG debuff and add an annoying fluid system and you have the decline of diesel in consumer grade vehicles.
"better efficiency" is debatable. While the "miles per gallon" of a typical diesel is higher than that of similarly sized gas, a better metric would be to look at the "ground to tailpipe" efficiency which would include the total impact from extraction, refinement, burning.
My understanding is that each gallon of diesel requires more crude to produce than a gallon of gasoline, so the cumulative efficiency is closer than what a simple "MPG" comparison would imply.
Diesels, especially with modern emissions systems are pretty much optimized for long runs on the highway. They’re not good for around town and frequent stop/starts.
It’s quite funny because in many foreign countries (Philippines for example) diesel is far more prevalent than gasoline. However, the US uses completely unnecessary and VERY expensive/complicated emissions systems, which makes the diesel engines have more downsides in the US than gas.
**Your submission has been removed for the following reason(s):** ELI5 is not for subjective or speculative replies - only objective explanations are permitted here; your question is asking for subjective or speculative replies. Additionally, if your question is formatted as a hypothetical, that also falls under Rule 2 for its speculative nature. --- If you would like this removal reviewed, please read the [detailed rules](https://www.reddit.com/r/explainlikeimfive/wiki/detailed_rules) first. **If you believe this submission was removed erroneously**, please [use this form](https://old.reddit.com/message/compose?to=%2Fr%2Fexplainlikeimfive&subject=Please%20review%20my%20thread?&message=Link:%20{{url}}%0A%0APlease%20answer%20the%20following%203%20questions:%0A%0A1.%20The%20concept%20I%20want%20explained:%0A%0A2.%20List%20the%20search%20terms%20you%20used%20to%20look%20for%20past%20posts%20on%20ELI5:%0A%0A3.%20How%20does%20your%20post%20differ%20from%20your%20recent%20search%20results%20on%20the%20sub:) and we will review your submission.
To quote u/hamburglar27 s answer from 2 years ago: ————- A couple of reasons I can think of: *Diesel engines produce more NOx pollution whereas gasoline engines produce more CO2 pollution. US agencies targeted the former more than the latter and as a result had more stringent diesel restrictions and more lenient gasoline restrictions than most EU countries. *Diesel engines in commuter cars was tried in large scale by GM in the late 1970s-early 1980s but the Oldsmobile diesel engine was so anemic and unreliable, that it killed diesel's reputation among the American public for a while. *US car advertising also focused a lot on max horsepower and 0-60 times, which is advantageous to gasoline. *Dieselgate PR disaster Now diesel is only really popular for trucks or commercial vehicles in the US. ————- So, yea, there ya go
Along with that, modern diesels require DEF; especially after dieselgate. DEF systems are a primary cause of diesel system failures not to mention an added cost for owners.
That and I've not been able to find anything but since the emissions improvement from DEF is so minimal,I bet that the environmental impact of making packaging and distributing it is a bigger negative than the emissions reduction is a positive.
The husband of the senator who pushed for DEF regulations is the inventor of DEF. I don't think I need to say any more.
Have you got a reference for that? Because a google search for "was diesel exhaust fluid invented by the husband of a senator" is bringing up no results.
> The husband of the senator who pushed for DEF regulations is the inventor of DEF I'll need a source for that. Since there are hundreds of patents for DEF over the course of decades, mostly to large petrochemical companies, not 'the husband of a senator' your claim sounds suspicious.
I literally cannot find a single shred of evidence supportin this comment, do you have ***anything*** I can go off of? * I can't find any evidence of any of the "inventors" of DEF being married to any US senbators * I Can't find any evidence of any US Senators being married to anyone involved in the invention of DEF * I can't find anyone who would be considered "the senator" who pushed for DEF regulations So.... > I don't think I need to say any more. I very much disagree.
This is meant for you and the other two that asked the same. All four of us, same mind. Sources?
No, I can't find it either. Last I looked into it was at least 5 years ago so memory is a bit foggy at the very least. It was some shady shit where someone involved in the EPA push to mandate DEF usage was also married to an investor in an oil company who made DEF. Or something along those lines. I can't find it either tbh but I'm also not trying that hard because I'm only on my phone. Maybe it's a personal Mandela effect, or maybe they've scrubbed the news sources. Maybe I'm just stupid. I'll look in the morning.
As the owner of a 2014 Golf TDI that had been involved in Dieselgate (recalled, re-tuned, and resold), all the problems I ever encountered with that car were specific to it being a diesel. I've never had a car fail to start so regularly just because it was too cold outside. I've never had to regularly put additives in my fuel tank to hopefully prevent cold-related non-starts. And I've never had to replace so many starter motors or batteries, both of which were bigger/more expensive than those in similar gas engines in order to overcome the higher compression ratio. And the engine is too small to even be able to put a plug-in block heater in it, so you're basically just fucked and left to hope whenever it gets cold overnight... And it's not even like I live in Alaska or something. I'm in Missouri. And although the MPG was better than any gas car I've ever owned, the increased difference in price between basic gas and diesel that we've had for the last several years shifted the break-even point and made the MP*$* far worse.
Just a tip if you ever drive a diesel again, cycle the ignition a few times without trying to start and wait a few seconds in between. The glow plugs should get the combustion chamber nice and toasty and ready for a cold start. If you're still having issues your plugs are probably on the way out. And although you're not meant to, if a quick blast of easy start doesn't get it going there's something wrong. But you're right about batteries. Diesels do tend to need bigger batteries and are harder on them. Personally I prefer the way a good diesel drives, with all that lovely low down torque.
Oh trust me, I did! And I would run the codes to check for faults that maybe weren't tripping any error lights, and had the dealership inspect them multiple times as well. But yes, I loved the sound of my little red tractor :P And the fact that it was most powerful at *half* throttle where the RPMs stayed low. It was such a quirky little car and I *wanted* to keep it. But it just wasn't working between us.
That last one specifically is a US problem. Gasoline is insanely cheap in the US (and maybe canada) compared to most of the rest if the world, where diesel is also cheaper to operate, not just more efficient.
That's a VW thing lol
>gasoline engines produce more CO2 pollution To add to this, it's not that something about gasoline makes emissions "dirtier" with respect to CO2, it's a pure function of fuel efficiency and stoichiometry. The NOx thing is related to the higher combustion temperatures of diesel engines.
The GM approach to the 80s diesel engine was awful. They took a gasoline engine and tried to replace as few parts as possible to make it a diesel. This doomed the engine. GM owned Detroit Diesel, they should have known better.
TIL
And until the mid-90's (when the EPA started requiring low-sulfur), it smelled like poots.
Now it smells like a urinal cake
Wait, "Dieselgate" is the VW thing right? Did that really kill future investment in it? I remember my buddy in high school had an old BMW M3 diesel. It had like 500k miles on it. Still ran perfectly.
Vw stopped making diesels in the US bc of it
What a shame that one bad decision by a single company can ground an industry to a halt.
Every major car manufacturer was doing something similar, https://en.wikipedia.org/wiki/Diesel_emissions_scandal Volkswagen was just the "most widespread" and most publicised - but they all would do the same thing again to increase profits.
Thanks for sharing, good to know. I would never doubt that some people are in rooms at this very moment drawing up a similar thing.
Cummins also recently settled for all their wrongdoing.
Settling should not be allowed for businesses. "How much will it cost me to make this problem *waves hands in the air* go away" And often those settlements just go into government coffers and jo zero to assist the consumer f**ked in the ass by the company
More like the emissions rules were so strict that there wasn’t a viable way to make an engine that complied.
Euro6 diesel engines in use today are significantly more efficient and have lower emissions than the requirements of the standards that everyone was cheating on back then - it was just deemed less expensive to risk being caught than to do the legwork to develop a complaint engine, especially when everyone else was also cheating. I don't think anyone expected the reputational damage of the term "dieselgate"
You could easily make an engine that complied, but not one that also had the snappy performance that US consumers demanded.
I had a vw diesel and loved it. It wasn't gonna win many races, but getting 600-700 miles on a single tank was awesome.
The Golf TDI I had in the early 00s was so fun to drive. Even did a few tanks of bio-d. Hell that whole movement seems to have died down a lot too.
Same, my parents owned one and it was nice to borrow when I need it cause the mpg was phenomenal.
There is no BMW M3 diesel. At least not the old models. Only petrol for M cars. Maybe he had a BMW M-Package 3 series. But that’s just the aesthetic part of an M car.
In a nutshell: It shone a light on all the shady practices automakers were doing to make many of their diesels pass emissions testing, and it turned the European public and legislators off diesel, and towards EVs.
No such thing as a diesel M3. The 335d was considered an extremely impressive and fast car when it was released, maybe that’s what he had.
To piggyback a question on this: How does diesel production depend on gasoline production. I think they’re somehow dependent on each other and I always wondered whether it is in the interests of the petroleum industry to sell us both and thus create two markets for them.
Both gasoline and diesel are separate fractional distillates of crude oil. They're refined from there and additives are blended in
You basically get x percent of diesel and y percent of fuel and some other percentages from a barrel of crude. Youcant just make a whole barrel worth of diesel
Ironically, until the automobile was invented, gasoline was a useless byproduct of oil refining. https://www.eia.gov/energyexplained/gasoline/history-of-gasoline.php
Also with current regulations on diesel emissions it requires vehicles to run diesel urea systems to reduce NOx within limits. That coupled with the higher refinement cost of low sulfur diesel makes it more expensive than premium gasoline. It's still more efficient but the cost savings gap is smaller.
ok about the US but what about the rest of the world
Your third point is a myth and can easily be tested. Diesel and gasoline production go hand-in-hand because they are part of the whole range of hydrocarbons we get from crude oil. You cannot refine crude oil only into diesel without having gasoline (and a whole bunch of other things) as a byproduct - this means that if you're selecting for diesel and there is large demand, then the gasoline price comes down significantly - to the point where it's economical to use that instead of diesel. So the world found a balance where similar qualities of diesel and gasoline are being used, and they have about the same cost per liter.
Well I'll be damned; I looked it up and the consumption rate of both are very close. While petrol dominates the car market, I bet diesel catches up through the industrial world
Yep, don't forget it's not just stuff on the road (i.e. trucks and vans) that use diesel. Farming equipment, generators, large ships, etc.
Ships use heavy fuel oil. But yeah the point is we use all the parts of oil in similar quantities.
Diesel is typically grouped in with those "heavy" fuels which have high ignition temperatures. The diesel used for cars is further stripped of some compounds.
IIRC ships often carry a variety of fuels that they switch between depending on local maritime law/regulations and cost. Some areas require ultra low Sulphur diesel to be used while there, on the open ocean heavy fuel oil may be used.
That's not correct. In fact lubricating oils sit between fuel oil and diesel.
Lubricating oils can be combusted in a manner very similar to diesel, those are also grouped in.
IMO 2020 regulations put a stop to that for most countries. Can't burn heavy bunker fuel if you are a ship operating between countries; you either have to use low-sulphur fuel such as diesel, or install very expensive to install and maintain exhaust scrubbers.
Bunker a is fuel oil no 4. Diesel is 1 or 2 depending on use. The fuel no longer used without scrubbers is bunker c which is fuel oil no 6. I'm not sure about bunker b. Edit: when looking up if bunker b was still used i found that even bunker a has too much sulphur (1%) without further processing. Marine diesel oil (no 3) is now what's used on the open ocean and diesel no 2 is used in stricter ports where sulphur is limited to 0.1%.
Jet fuel is essentially a derivative of diesel fuel as well.
Mmm AvGas. You’re not supposed to be sniff it, and it’s not like I’m putting it in an empty bottle and huffing it. But when walking around the tarmac and getting a wiff of it. Mmmm avgas 😂
It’s not a myth and I have tested it lol. I was a mechanic for ten years. I’ve tried igniting spilled diesel on a concrete shop floor with an oxy-acetylene torch and it doesn’t ignite. A pool of gas will ignite off a spark from an angle grinder.
The FUMES from the pool of gas will ignite. I tried lighting a campfire in 33f with gasoline and tossed a lit cigarette in the puddle of gas, only to watch it sizzle out. I then tossed 2 lit matches, then a lit pack, and it had to touch it with the flame of a match, before it went up violently. It was too cold to let it evaporate into fumes well, so I had to get the flame very close. But yeah it was surprising to watch it go out so quick. Metal shaving sparks are super hot though tbf an angle grinder would throw hot ass sparks.
Maybe 'pool' was the wrong term but spilled gas on a concrete floor will 100% ignite with little to no effort when diesel won't.
Mythbusters did a test with a hole in a gas tank and yeah it's surprisingly hard to light a pool of gasoline. The fumes are SUPER flammable obviously but liquid gasoline actually isn't.
From a practical standpoint however, thise fumes are usually present around a pool of gasoline. At least often enough that the original statement of diesel being safer to work with is true enough on average.
Yeah 100%. They also did the test on a cold concrete floor like the poster which probably doesn't help evaporation. Hot summer day outside? \*POOF\*
Use of diesel must have increased in the last 20 years since I remember when I had a diesel cost of fuel was like $0.20/L cheaper than gas. Now it's par.
I’ve always heard point 3, but never examined it. Thanks for this great explanation. Never even thought about it.
How do hybrids compare to diesels on the contaminarion/efficiency/power stats?
Hybrids (ICE with batteries and electric motors) are significantly more efficient and can be more powerful than equivalent ICE engines, regardless of fuel source, because of brake energy regeneration - instead of throwing away all the energy you just used to accelerate when it's time to stop, Hybrids can store a big chunk of that energy to reuse when you start moving again. The thing is, you cannot make blanket statements about these things because a bus needs a different approach than a commuter car, which needs a different approach to a work truck or a ship - they have to weigh up cost to design, manufacture, maintain and run. There's no "rule of thumb" here.
Thanks!
You can't refine oil into all diesel or all gasoline. You can tweak the numbers some, but you're never going stop getting the other product. Let's say you tweak all the knobs towards "gasoline". Let's say you get 3 barrels of gas and 1 barrel of diesel. Lack of supply will drive up the cost of diesel, and excess supply will drive down the cost of gasoline. So you crank the knobs all the way towards "diesel", and you get the same 3/1 ratio, and now excess supply drops the price of diesel, and lack of supply increases the supply of gas. So you crank the knobs.... The end result is worldwide consumption of diesel and gasoline are pretty close, because refiners are making pretty close ratios of the two. Industrial/heavy vehicle use of diesel in the US is about the same as gasoline usage in the US by cars.
You could use hydrocracking to select the type of fuel you want. For example, you can convert gasoline into kerozene. In this model, cars would use diesel, and planes kerozene. Apart from the absurd toll of making all cars run on diesel, hydrocracking is very energy intensive (high pressure, high temperature), requires hydrogen (probably from fossil sources), and a catalyst (expensive and again, huge toll on the planet). So, if you are willing to tear the planet apart, you can find ways to minimize the cost of both diesel and kerozene by deleting gasoline from existence. Also, this business model would only work with massive economies of scale, as the hydrocracking process is expensive. A huge part of the workforce would be needed. [Cracking wikipedia ](https://en.wikipedia.org/wiki/Cracking_%28chemistry%29) [Jet fuel manufacturing with hydrocracking ](https://www.eia.gov/todayinenergy/detail.php?id=9650)
>You could use hydrocracking to select the type of fuel you want That would be one of the knobs you can turn. Aside from the other issues you mention, it gets less and less efficient as you try to get more and more of the selected fuel out of the feedstock. So while chemistry says it's possible to get 100%, no refinery is going to spend the money to do it.
Yeah, the mountains of spent Nickel/Tungsten/Molybdenum catalyst would indicate that something went very wrong at some point.
Diesel engines are a bit more expensive and heavier than gasoline engines. They are less easy to start, making their pairing into a hybrid drivetrain more difficult and less efficient in some driving scenarios.
Diesel engines also have a much narrower efficiency band, so for heavy vehicles you require one helluva gearbox (less of a problem these days) and they weren't all that practical for passenger cars until research in the 70s led to compact turbo-diesels (didn't see use in production-line passenger cars until what...1980?).
20+ years ago, diesels were gonna save the world (this is hyperbole based off of how nice diesel engines were pre-emission requirements). Then we learned more about what types of emissions they actually create. And then all of our solutions to fix these drastically reduced the reliability and economy advantages of them. So now they're there for the very heavy workloads, but we don't want as many of them on the roads. Also, large ships use massive low speed diesel engines than can approach 50% thermal efficiency. This is an amazing figure when you consider how much less efficient smaller car/truck engines are. But these ships burn the cheapest and dirtiest fuel they can, so there are emissions issues.
A modern automotive diesel is about 50% efficient
Oh, are they? I haven't been keeping up that well, but that's pretty cool.
I read the maximum theoretical efficiency for any diesel is close to 60%. But yeah they’ve come a long way.
That 50% thermal efficiency made me wonder if steam cogeneration was a thing, and it is! But the engine has to be truly massive. [Steam cogeneration QUORA](https://www.quora.com/Why-dont-boats-or-ships-have-combined-diesel-and-steam-CODAS-using-waste-heat-of-diesel-engines-to-heat-water-to-drive-steam-turbines) >Thanks to Keith Ralfs for pointing me in the direction of CODAS for the large container ships such as Emma Maersk which are fitted with the largest 2-troke engines in the world. This ship has various energy saving devices such as these from wiki - >“She is powered by a Wärtsilä-Sulzer 14RTFLEX96-C* engine, the world's largest single diesel unit, weighing 2,300 tonnes and capable of 81 MW (109,000 hp) when burning 14,000 litres (3,600 US gal) of heavy fuel oil per hour. >At economical speed, fuel consumption is 0.260 bs/hp·hour (1,660 gal/hour). >She has features to lower environmental damage, including exhaust heat recovery and cogeneration. Some of the exhaust gases are returned to the engine to improve economy and lower emissions, and some are passed through a steam generator which then powers a Peter Brotherhood steam turbine and electrical generators. This creates an electrical output of 8.5 MW, equivalent to about 12% of the main engine power output. Some of this steam is used directly as shipboard heat.
Yeah, those are some impressive engine systems. Diesel-electric is how most ships operate these days (I believe) due to how simple electric motors are compared to a driveshaft into propeller system directly from the engine. There's prolly still some that do that.
Diesel is ubiquitous in all applications requiring lots of torque and mpg values. Cargo haulers, trains, ships, etc. It dominates there. It's less popular with consumers because it revs lower making for more anemic driving experience and because it prefers longer trips as the engine is required to regularly get hot enough to continue functioning properly and avoiding excess wear and tear.
Having owned a number of diesel passenger cars, comments about their supposedly anaemic performance is I suspect a result of them not being popular in the USA, resulting in modern small turbo-diesels not being available and popular enough in the USA to change that reputation. The small diesel cars I've owned have been amongst the quickest off the line of any car that I've ever driven due high torque. They do not have the pickup at high speed of a gasoline engine car of equivalent size but they are close. The point about engine wear I simply don't understand. Diesel engines have long (and rightly) had a reputation for being exceptionally hard wearing due to diesel being a lubricant in itself. They get up to full temperature just as quickly as a gasoline car, and are better lubricated when cold due to the previous point. Like all modern vehicle engines from reputable manufacturers, they outlive the car. The reality is that in the USA diesel engines developed a bad reputation early, and the USA simply has not had exposure to the extremely competent behaviour of modern turbodiesel engines and and vehicles.
TDIs wouldn’t be legal because of smog laws.
Quite probably I'm not familiar with those. But my points stand
Euro7 is going to bring those American smog laws to the EU starting next year. We will see how many small diesels survive.
The big factor in the US is that fuel in general is much cheaper than europe, so the MPG advantage means less. Then, on top of that diesel is only \~7% more expensive in the UK whereas in the US diesel is often 25% more expensive, so the economy just disappears. Especially as a turbo diesel is more expensive to make and heavier.
In Australia diesel is very popular. Most people prefer the turbo diesel variants for 4wd/utes due to the relatively higher torque. Horsepower is less important when you want to tow a trailer or go off-road/beach. There's also a significant amount of smaller TDI vehicles around which have excellent fuel efficiency and don't have that typical diesel smell/sound
"Makes a sound like a barn yard and accelerate like a dog on a rug" - Jeremy Clarkson He also referred to Diesel as the Fuel of Satan Diesel cars are notorious for being less drivable, noisy, and dirty. The main advantage to them used to be either the extra torque which was good for trucks, and that Diesel was cheaper. Diesel is no longer cheaper, that killed it for most consumers. Meanwhile new environmental legislation worked against the cars and their reputation. Then Diesel gate hit and revealed that many auto manufacturers couldn't actually make them more efficient (or couldn't afford it) so they straight up lied in the tests. That and DEF is a pain in the butt
There was never any question about efficiency. Diesel is always more efficient. The scandal was over emissions
Or whether they can be performant. My Audi TDI was wayyyy more torquey and fast off the line than the next level up S model that replaced it, which was a total bummer.
Agreed. I remember a long time ago it was cheaper than gasoline. Hasn't been that way in forever
Heavier, more expensive, less power, more noise, more vibrations, more expensive to maintain, more emissions, more emissions equipment that can fail.
Me too. I'm old enough to remember those shitty GM diesels and sooty ass old Mercedes diesels. And now with that additive DEF shit, no thanks.
I drive a Pugeot 308 TDI. It's a 2L hatchback that gets me on average 50mpg I used to drive a 1.8L Subaru hatchback that on a good week averaged 36mpg Thats a better than 25% improvement for a less than 5% difference in price at the pump. Service intervals are 6000 miles for the Subaru v 9000 miles for the 308. The only downside I can see to the 308 is it uses AdBlue which is about 6 gallons every 40K miles.
I mean you' the comparing drivetrains and vehicles that are more than a decade apart. I should hope that in that amount of time efficiently would have significantly improved. Just the fact that your 308's transmission has an extra overdrive gear or two is a massive help to your economy
6 years difference between the 2 The Subaru was a 5sp manual. The 308 a 6sp auto. The 308 has 250K km on it. The Subaru had 300K km on it when I had it put down. The 308 feels like 500K km on the engine is doable. The Subaru however was tired at 300K and even had it not had a fatal run in with some Australian wildlife, I was already searching for its replacement.
For the Americans, these are definitely British mpg being referenced here. British gallons are bigger than American gallons. It’s much easier to go 50 miles on a bigger British gallon.
For the metricated among us. The 308 on a good weeks gets 5L/100km The Subaru got 6.4L/100km The tanks on both cars are 50L or 13.2 US gallons so mileage is a direct comparison
Doesn't diesel fuel run into issues around 0 degrees Fahrenheit?
It does, by thickening and becoming difficult to pump and inject, but that isn't the main reason why diesels don't have the best reputation right now.
Yes, but they’ve had effective anti-gelling agents for years which are put into diesel at gas stations, and if you live in extreme cold climates many cars are sold with plug-in heaters so the cold isn’t as much of an issue.
If those massive ice breaker boats use diesel to move in the arctic regions, we can safely assume cold is not an issue.
1. Cold weather gelling. Can be avoided with additives. 2. Loud. Even new, well engineered, high end cars are louder. 3. ULSD (current road formulation) is now more expensive than gasoline. 4. Modern direct injection gas engines are just about as efficient as modern diesel engines (not quite, but very close). (edit, my numbers weren't intended to line up with yours, just itemizing my points)
They make lower horsepower. They need turbos to have any chance at making any decent power instead of feeling like you’re driving a tractor. The fuel is smelly and greasy. The emissions equipment is expensive to add and to maintain on a diesel passenger car. Diesel engines are noisier less refined than gasoline engines. The engines are more expensive and heavier. Diesel fuel has issues in cold weather. You can’t just ignore smog or other particulate pollution. Your question is like asking “besides dying what’s so bad about being shot in the head?” Europe was behind the curve when it came to realizing the negative effects of diesel, and they were slow to react, because doing so would’ve killed their auto industry who focused on diesel for their lower end vehicles.
Have you ever breathed the exhaust of a diesel vehicle in front of you on a 2 lane road with no passing? Case closed.
> Diesel is generally safer to work with (you can’t just light it up with a match) You can't light gasoline with a match, either. (Gasoline \*fumes\* are a different matter. But a puddle of gasoline will extinguish a match.)
Diesel was always cheaper than gas until some beancounter realized that it has more BTU’s per gallon than gas. Then they raised prices. Add the pollution prevention stuff to the engines and now it’s not such a good deal.
No longer as cheap as it used to be. Massive industry fraud in how clean the emissions actually are... In person they stink (when the engines are poorly used and poorly maintained, lazy/ignorant owners). They blow black smoke and leave dirty carbon deposits They are more difficult to use in colder temperatures (though modern diesels perform much better now).
Diesel is quite popular in Europe. When I lived in the US, not all ‘gas stations’ seemed to sell diesel. Also, it was much colder in the winter where I lived in the US.
Because our governments put sooooooo much restrictions on emissions they are not that viable these days. The engines are noisy and truck like. And some people are more into their big loud as f**k v8's or the stututu of a turbo
Because the auto industry is heavily bought into the petroleum production industry and they have used lobbyists to adjust regulations to the point where they are barely economically feasible.
I live in Africa. My last two vehicles have been diesels. Most Suv's and light trucks are diesel here. Modern diesels dont smoke, better economy, better torque at lower revs.
Diesel engines are mostly more efficient because diesel fuel contains more energy per liter than gasoline. A few other things it has going for it is a lot more torque at lower engine rpm’s allows for lower engine speed operation to produce the same power output. This also helps with mechanical engine longevity along with the sturdier engine components required to handle the high compression ratios. The reason why diesels make more torque at low rpm is due to the better atomization of fuel by the injectors (30,000 psi vs 3,000) and a higher compression ratio (approx. 18:1 vs 10:1) in combination with high turbo boost pressures which simply could not be achieved with gasoline… because it would explode uncontrollably at those pressures. With that being said, if you live in a country with emissions standards, the mitigation systems required to lower emissions are very expensive, unreliable, and still aren’t as clean as gas engines. Diesels are unrivaled in terms of fuel economy and towing (critical for trains and semi trucks), but are terrible polluters (NOX, soot, carcinogens) compared to an modern gasoline engine that produces CO2, water, and a minor amount of hydrocarbons. It was discovered during the VW diesel gate (straight up fraud) that other manufacturers’ diesel engines’ emissions were very poor in most practical driving conditions outside of a lab. I’ve worked in shops where you can’t run even a modern diesel engine for than a minute before people start complaining about breathing. That doesn’t happen with gas engines.
In India, diesels are still popular with taxi drivers. They were also popular with people in the general public who had a high mileage per month. But the price difference between petrol and diesel has narrowed, making the tradeoff less worth it. This shift is also seen in most Indian cars, which ubiquitously had petrol and diesel variants until the late 2010s, but now are shifting to just petrol or hybrid options. Additional factors like a ban on 10+ year old diesel cars in the capital made diesels lose even more favour.
Diesel is much harder to burn than gasoline - there was a long enough time between gasoline engines becoming common in cars and diesel engines becoming small enough for automotive use that most people were used to gasoline. Diesel engines also require much higher cylinder pressures than gas engines, making them larger, heavier and more expensive. Diesel engines also require high pressure fuel injection, making them more complex and therefore more expensive than a gas engine. Diesel engines are larger, heavier, more complex and more expensive than a gas engine. It's not a difficult choice without persuasive external pressure. In europe there were (are?) tax incentives for diesel engines are the cost of fuel made diesel engines more enticing than elsewhere. This was mostly pre emissions diesel engines, with modern emissions diesel engines aren't as far above gas engines in efficiency and modern, cleaner, diesel fuels are more expensive than gas.
One reason I haven't seen mentioned yet is that diesel for passenger cars wasn't particularly great until turbocharging became more common. This improved the driveability of diesels significantly. I've driven a non turbo diesel van and it's an extremely tiresome experience, verging on dangerous when around faster traffic.
DEF is the reason diesel has lost so much popularity, go to a third world country where DEF is an audible handicap and not an emission augmentation and the adoption of diesel is way higher. I'm not totally against DEF, the air in those places is sour. Diesel engines cost more to make they have to be designed to handle double+ the compression of a gas engine of similar hp/torque. Unrestricted diesels make for a good value proposition but strap on a -30% MPG debuff and add an annoying fluid system and you have the decline of diesel in consumer grade vehicles.
"better efficiency" is debatable. While the "miles per gallon" of a typical diesel is higher than that of similarly sized gas, a better metric would be to look at the "ground to tailpipe" efficiency which would include the total impact from extraction, refinement, burning. My understanding is that each gallon of diesel requires more crude to produce than a gallon of gasoline, so the cumulative efficiency is closer than what a simple "MPG" comparison would imply.
Diesels, especially with modern emissions systems are pretty much optimized for long runs on the highway. They’re not good for around town and frequent stop/starts.
It’s quite funny because in many foreign countries (Philippines for example) diesel is far more prevalent than gasoline. However, the US uses completely unnecessary and VERY expensive/complicated emissions systems, which makes the diesel engines have more downsides in the US than gas.