A new study published by the Environmental Protection Agency indicates that modified diesel pickup trucks are contributing to increased levels of particulate pollution in the United States.
The EPA study, which was first reported on by The New York Times, found that an estimated 550,000 diesel pickup trucks have had their factory emissions controls removed or modified in some way over the past decade using aftermarket tuning devices. As a result, these modified trucks will emit roughly 570,000 tons of excess nitrogen and 5,000 tons of particulate matter over their lifetimes, which will have an air quality impact equivalent to adding another 9 million diesel trucks to U.S. roads.
The New York Times says the EPA first began looking into the illegally modified diesel pickup trucks after the Volkswagen diesel emissions scandal came to light in 2015. An industry-wide crackdown on companies manufacturing diesel engine tuning devices would be much harder than going after a major OEM like VW, however, as the devices are manufactured by a wide variety of companies that are usually quite small or may not be located in the U.S.
It’s not just diesel trucks that are having their factory emissions control systems re-tuned. Many of these companies manufacture devices that will reflash the engine control unit on a variety of vehicles, from turbocharged hatchbacks to commercial vans and almost everything in between.
“One reason it is difficult to estimate the full extent of tampering nationwide is that the Air Enforcement Division has reason to believe this conduct occurs within most or all categories of vehicles and engines, including commercial trucks, passenger vehicles, pickup trucks, motorcycles, forestry equipment and agricultural equipment,” the study found.
While many vehicles can easily have their ECU reflashed, heavy trucks are of the most concern for the federal environment watchdog, as they have larger engines that typically emit more emissions. Modifying the ECU on a diesel truck can not only rework the way the engine operates and increase emissions, it can also disable or change settings for crucial emisisons-reducing systems like the Exhaust Gas Recirculation system (EGR) or after treatment systems.
Aftermarket ECU systems like this can increase a truck’s horsepower or torque output. They can also be used to adjust the way emissions controls like the EGR system work and reduce the time and/or cost it takes to maintain or repair them over the truck’s lifetime, making them a popular modification among diesel enthusiasts.
General Motors offers diesel engines in both the light- and heavy-duty versions of the Chevy Silverado and GMC Sierra. The Silverado HD and Sierra HD are offered with a 6.6L L5P V8 Duramax diesel engine, while the light-duty versions of the trucks are offered with a 3.0L LM2 inline-six turbodiesel.
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Comments
We have all seen the 5 foot 6 inch guys with the 8 inch lifted diesel belching out a huge cloud of black smoke from the back or top of a modified stack.
the feds should step in and make these modification illleagle
After reading this article, i agree.
It’s been illegal ever since pollution controls were first mandated. I think you mean enforcing the existing laws.
Yes another solution might be imposing a tax on all carbon and using that money to clean the air
Plus with the price of Zero Emissions gas coming way down I think that another way to improve the environment would be to impose a carbon tax (on all carbon taken out of the ground) that slowly gets larger until it equals the cost of removing the carbon from the air. Then gas will cost more than it does now (because of how expensive carbon capture is) but it will let us decide what to do with our cars. In this plan you the consumer would decide what is best (most economical, most fun, ect.) car to to use and not let the government control you as much. And it would save the environment because all the carbon will be removed from the air.
If we both tax carbon and limit the road legal modifications to a reasonable amount it will allow people to have some control over there cars/trucks/SUVs but also protect the environment.
Ah duh. The R-N’s driving these trucks think it’s super cool to rev the heck out of them and watch the huge plum of black soot/smoke roll into the sky. Probably half the reason these people drive them anyhow, because it’s sure not for using them as a real truck in most cases.
It’s “compensation “.
What the report doesn’t mention is that with an optimal tune, the diesel trucks use 25-30% less fuel. How much does the reduced fuel consumption offset the increase in tailpipe emissions? I would actually like to know. There is more to global emissions than just tailpipe emissions.
It’s the same mentality as switching to a large electric vehicles in an area that burns coal for power, instead of buying a smaller ICE vehicle AND driving less. Overall… driving a smaller vehicle less miles COULD have a greater overall reduction in pollution.
Basically, running a diesel leaner is more efficient since there is more air in the cylinder which insulates the heat of combustion from heat loss from the cylinder walls. However, the hot air breaks down and forms nitrogen oxides. That’s why the most fuel efficient tune is not the lowest emissions.
The exact same thing happens in direct injection gasoline engines. Under high powers, they switch from fuel-saving stratified charge to conventional stoich burn mode because NOx and particulate emissions reach limits.
I understand the tune will produce more tailpipe emissions, I would like to know how the increase compares to the emissions saved by using less fuel. It would be nice to have all the facts, not just the ones the EPA wants me to have.
@Cdnsolman: I’m not sure how that would be calculated and I certainly won’t pretend to be an expert here. Far from it. What I will ask is when you say 25 to 30% less fuel, do you mean a tuned truck will get 25 to 30% more mpg? Huge difference there. Using 25 to 30% less fuel would equate to a lot less fuel overall. Using the same % you give, a truck getting 18 MPG highway (max) would be tuned and get 23 MPG highway max. Although that’s impressive increases, that extra fuel saved would never offset the billowing soot/smoke of the trucks we are referring to. I’ve sold Chrysler brand cars/trucks in the past and had numerous guys come in with tunes on the Ram’s.
The problem is that most of the guys doing these with the huge increase in exhaust emissions are NOT doing it for the better MPG. They are doing it for the show, the go, the burning rubber and yes, the huge clouds of black smoke coming out the back.
I think it’s very safe to say that we should all leave the trucks tuned to the factory for good reason.
We all know the smoke tune is stupid and that’s not what I was referring to. They also don’t discuss what type of tune in the article either. I live in northern Alberta, and we have major issues with the def freezing for 1/2 the year. Once frozen it does major damage. The tune my local shop does eliminates the def, and optimizes the tune for mileage and longevity.
I’m just curious the numbers, what type of tune are they referring to, what emissions exactly go up by 2000% etc.
I know VW tdi’s all got significantly worse mileage after the “fix” for emissions, and I was always curious what the comparison was.
I should say, my diesel (pre-def) is all stock and don’t plan to tune it, but Im still curious about all the details.
I would be curious to know as well. From what I see and the article above, it’s something the EPA should work on I guess. You do have great points.
As stated in the article, 550,000 trucks are putting out emissions (I assume excluding co2) equal to 9 million stock trucks. So if the get 20% better mpg, MAYBE that means 20% less CO2, at the expense of 20000% other emissions.
If the article is using smoke tune references for it’s emissions calculations then it isn’t really what I’m trying to compare. (I’m not claiming truth or knowledge to either argument, just pointing out a lack of detail in the released information)
It could be 1 very minute “emission” that goes up significantly but actually has very little impact, it could be a major cancer causing toxin. I would just love to see more details.
I’m not claiming that a tune is the same as not tuned because they do better on fuel, I know that’s unlikely, but I’m curious all the numbers.
Sometimes the big picture isn’t seen when talking about environmental impact.
(Like the water pollution caused by manufacturing solar panels to reduce air pollution)
Emissions deleted trucks put out less CO2 (good globally, irrelevant locally) but WAY more particulate emissions (bad locally, irrelevant globally). Particulate emissions are shown to increase prevalence of dementia/cognitive decline/heart disease. This is very bad in any kind of city, but probably not that big of a deal if say farm use only or operating in the woods where it can diffuse.
Nothin like rollin coal in Murica!
This story is a reminder that General Motors CEO Mary Barra speaks from both sides of her mouth, Barra said General Motors wasn’t interested in an EPA rollback under the Trump Administration yet the company is making after market changes that increases greenhouse emission.
In other news, when you get killed, you die…. the more you know
The tuning market is MUCH smaller than it was. The EPA 2007 rule engines (MY 07, 08,09) were unbelievably terrible for both fuel mileage and reliability didn’t matter what OEM. Reducing particulates and reducing NOx are not complimentary…when you fight one you usually increase the other. When the 2010 engines came with DEF, the strategy changed to fight the particulates in cylinder (a good efficient lean burn) and deal with the NOx outside the engine (using DEF in an SCR catalyst). Yes, early DEF systems were a problematic for some but they got a LOT better. Given the HP and reliability available in a diesel pickup now, the only guys tuning now are power nerds….because basic reliability and performance are there now, right from the factory. The guys who tune to “roll coal”….they are just afew but very visible neanderthals, and their time is rapidly approaching zero as the trucks are way harder to tune, and any company making the investment to do it, has too much on the line to risk it. The big tuning houses now are all emissions on tuning.
The EPA went in too hard, too fast on Diesel engines.
This is a natural response to costly and often unreliable emissions controls that rob efficiency and performance from the owner.
Next….EPA says that electric vehicles create too much Ozone from the electric motors, back to horse & buggy.
Oh wait, methane emissions can escalate as well as horse waste on the road.
Bicycles are the answer!
EPA needs to be DEFUNDED!
I have talked to many people that have problems with diesel trucks from GM.A lot of $2000.00 repair bills on their trucks more than once.Gm should repair these problems because it is in their design to fail problem.Maybe put some of that bail out money to correct their problems with emissions.
I can understand doing a EGR or DPF delete for economic reasons, better fuel economy and reliability also. But tuning for more smoke is dumb and it’s going to cause a clamp down on everyone.
The main reason other then added power for these tunes is to make them more reliable – there’s nothing like driving out in the middle of nowhere when a check engine light comes on with at warning that your truck will be limited to 12mph in the next 40 miles, then in 50 miles it will be limited to 3mph. If the emissions control devices were more reliable and wouldn’t leave you stranded there would be less of a need for these tunes that delete the emissions systems. It’s not all about rolling coal, it’s making them reliable and getting more power at the same time.
Being an owner of a deleted/tuned Duramax, I have to say it was the best decision I could have done. I own a 2012, bought it new. Deleted it in 2014, when it was made available for the LML. I do not drive it eveyday, just for towing and hauling. I only have 50,000 miles on it. I like mileage and knowing the longevity of the motor. I do not like smokey tunes, it wastes fuel. I also am not looking for a big number power tune either. The EPA since 2007 has been hell bent on diesels. Putting an inefficent emission system in place is not the answer. I truly do not know what would be a good solution. GM has had many emission related issues in the past. Time will tell, I sorry but EV is not the anwser either.
I believe what the article statistics don’t take in to consideration, Is the large percentage of vehicle owners who delete their trucks primarily for better economy and reliability. And though they very likely have slightly higher carbon and NOX emissions, they sure save a bunch of raw materials. No more DEF heaters, DEF pumps, DEF injectors, EGR valves and coolers, not to mention the occasional plugged DPF . Not to mention saving an engine now and then because you can see the smoke when an injector is stuck and get it replaced before it melts a piston. The reason these folks go unnoticed is they drive their trucks like they were intended to be driven and run clean tunes. And yes 20% increase in fuel economy is very common. In fact for the troublesome 07 – 10 trucks. We have often heard of many increasing more like 50%. Going from 12-13 mpg to 18-19 mpg. Many of these folks though will admit it’s making much less financial sense to delete their trucks now than it did 10 yr. ago since the emissions system reliability has increased exponentially and with SCR, regens are much fewer and with much better factory tuning these big diesels are starting to tip into the lower 20 mpg range stock running empty. But like the man from Alberta said there are still issues here and there like DEF in cold weather etc. EPA regulations have push tech improvements that all us truck guys have benefited from but there has to be some flexibility. So far that flexibility has been in the enforcement of the law. But as the law cracks down on the coal rollers it also hurts these good ole boys.
These mods done to HD diesel trucks absolutely kill the trade in/used value of them. We don’t keep them when we trade for them because to retail it we first would have to re-install the proper equipment and program them the way they were supposed to be. But even then if they have a problem with it the ECU remembers all of that. It can cost as much as 10k or more to put them back the way they are supposed to be.