EPA Admin Lee Zeldin Makes it Clear Deleted Diesels Illegal After Rollback

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October 13, 2025
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5 comments
Deleted Diesels Illegal After Rollback 1

A long running question has been answered with EPA Admin Lee Zeldin making it clear diesel emissions rules will stay and deleted diesels are illegal even after announcing a plan to roll back certain rules.

The proposed roll back of the 2009 Endangerment Finding announcement caused quite the stir among diesel fans with Zeldin stating “It won’t be rolling back anything, it will be ELIMINATING EVERYTHING.”

However, that’s not what is actually in the proposed plan.

What did Lee Zeldin make clear?

Deleted Diesels Illegal After Rollback 2
EPA Administrator Lee Zeldin put his proposed plan into writing and it clearly spells out deleted diesels are still illegal. (Photo courtesy EPA)

The proposed roll back is now available for the public to read as in the Public Register. It lays out the arguments for the roll back, the proposed plan on how it will be rolled back, the public hearings for comments and what sections will be altared of the Clean Air Act.

EPA Administrator Lee Zeldin put his name on the document and right below stated the agency plans to amend certain sections of the law.

This is quoted from the document:

“PART 86—CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES

§ 86.007-11

Emission standards and supplemental requirements for 2007 and later model year diesel heavy-duty engines and vehicles.

(1) The engines must be of a configuration that is identical to one that is certified under 40 CFR part 1039, and must be certified with a Family Emission Limit for PM of 0.020 g/kW-hr using the same duty cycles that apply under 40 CFR part 1039.”

What does all of this mean?

Deleted diesel illegal 4
The Federal Register document. (Screenshot by Tim Esterdahl)

This language is government speak and means this.

Family Emission Limit (FEL): This is an emissions value chosen by the manufacturer for a specific “engine family”. An engine family is a group of engines with similar characteristics that are certified together. The FEL serves as the emissions standard for all engines within that family for certification and compliance purposes.

PM: This stands for Particulate Matter, which is a key regulated air pollutant. PM consists of tiny solid and liquid particles suspended in the air, which can cause respiratory and other health problems.

0.020 g/kW-hr: This is the specific measurement for the PM emissions.

0.020 g: The mass of particulate matter, in grams.

kW-hr (kilowatt-hour): The unit of work output from the engine.

Meaning: The engine is certified to emit no more than 0.020 grams of particulate matter for every kilowatt-hour of work it produces. 

40 CFR part 1039 is the U.S. Environmental Protection Agency (EPA) regulation that sets standards for controlling emissions from new and in-use nonroad compression-ignition (diesel) engines. These engines are found in a wide variety of equipment, including construction machinery, farm tractors, forklifts, and generators.

Diesel Emissions Will Stay, Deleted Diesels Still Illegal

2007 and newer diesel trucks must meet current emissions standards now and into the future. (Photo courtesy Stellantis)

Putting it all together, this translates into a clear statement that the rules aren’t changing for all diesel engines including on-road and those used in that specific section.

Today, diesel truck engines are legally required to produce less than 0.020 g/kW-hr of particulate matter (PM) and will be in the future even if the proposed 2009 Endangerment finding is rolled back.

According to the proposed changes above or non-changes for diesel truck owners, nothing has changed.

If you tamper with a vehicle’s emissions control system, causing it to produce more than 0.020 g/kW-hr of particulate matter (PM) it is a Federal offense that can lead to substantial civil and criminal penalties.

As Diesel influencer Heavy D found out, it isn’t just a criminal matter, but also can be a serious civil matter.

Why delete diesel emissions equipment?

Deleting diesel emissions equipment 4
Diesel truck owners use their trucks for work and anything costing them additional money and downtime is a big issue. (Photo courtesy Ram trucks)

If the diesel emissions equipment reduces the harmful pollutants making air safer for people with health issues and less harmful for the environment, why would owners want to remove aka delete diesel emissions equipment?

The simple answer is many see these systems as reducing the reliability of their diesel engines as well as reducing the performance of the engines in terms of power and fuel economy. For these owners, the truck is their livelihood and the emissions equipment causes them increased costs to operate their trucks as well as can cause increased repair time.

When faced with thousands in repair costs versus removing a part, many diesel truck owners opt to remove the part.

They also argue over the proposed scientific benefits of the emissions equipment and challenge the conclusions the equipment serves any benefit. Plus, if the U.S. Military and first responder vehicles get waivers to not use emissions equipment, why do consumers and commercial business have to use it? It all seems unfair to them.

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Avatar of testerdahl
testerdahl

Administrator

2,716 messages 4,601 likes

A long running question has been answered with EPA Admin Lee Zeldin making it clear diesel emissions rules will stay and deleted diesels are illegal even after announcing a plan to roll back certain rules. The proposed roll back of the 2009 Endangerment Finding announcement caused quite the stir among diesel fans with Zeldin stating “I won’t be rolling back anything, it will be ELIMINATING EVERYTHING.” However, that’s not what is actually in the proposed plan. What did Lee Zeldin make clear? The proposed roll back is now available for the public to read as in the Public Register. It […] (read full article...)

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Avatar of TheDo114
TheDo114

Well-known member

762 messages 1,203 likes

Big nothing burger lol. I suspect people will not be happy about that online.

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Avatar of testerdahl
testerdahl

Administrator

2,716 messages 4,601 likes

Big nothing burger lol. I suspect people will not be happy about that online.

Funny you should mention that. One of the channels that hates me did a video on this calling me an "influencer who hates trucks and especially diesels." This was after a bunch of his fans sent him my video. He declared that it is LEGAL to delete your diesel and all you need to do is take your truck to the manufacturer and have them "certify" it after it has been deleted. Then you are all set.

I can't find the video because I blocked his second channel. Auto bit daily or something.

I only learned about his channel on the Ram RHO forum after he declared all of our RHO's were junk and failing. Then, he claimed Chrylser was going to start making everything down 35% down starting in January or February.

He got really mad at me when I asked him who his sources were in one comment. That's it one comment. Declared me an a-hole. Sent a bunch of his followers over to call him all sorts of names and started a YouTube war or something.

Now when I post a story and video like the above, I get called all sorts of names and they believe him. Ok. Believe what you want.

I remember back in the summer when I covered this. People declared me to be a hater of trucks, hater of diesels and just wait 45 days and automakers were going to start shipping 2026 models without emissions. Just you wait TIM IT IS GOING TO HAPPEN!

2026 models are shipping with emissions.

Reply 3 likes

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Avatar of TheDo114
TheDo114

Well-known member

762 messages 1,203 likes

Funny you should mention that. One of the channels that hates me did a video on this calling me an "influencer who hates trucks and especially diesels." This was after a bunch of his fans sent him my video. He declared that it is LEGAL to delete your diesel and all you need to do is take your truck to the manufacturer and have them "certify" it after it has been deleted. Then you are all set.

I can't find the video because I blocked his second channel. Auto bit daily or something.

I only learned about his channel on the Ram RHO forum after he declared all of our RHO's were junk and failing. Then, he claimed Chrylser was going to start making everything down 35% down starting in January or February.

He got really mad at me when I asked him who his sources were in one comment. That's it one comment. Declared me an a-hole. Sent a bunch of his followers over to call him all sorts of names and started a YouTube war or something.

Now when I post a story and video like the above, I get called all sorts of names and they believe him. Ok. Believe what you want.

I remember back in the summer when I covered this. People declared me to be a hater of trucks, hater of diesels and just wait 45 days and automakers were going to start shipping 2026 models without emissions. Just you wait TIM IT IS GOING TO HAPPEN!

2026 models are shipping with emissions.

Lollll.

Like any manufacturer would re-certify a vehicle after sales.

Reply 3 likes

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Avatar of testerdahl
testerdahl

Administrator

2,716 messages 4,601 likes

Lollll.

Like any manufacturer would re-certify a vehicle after sales.

He was DEAD serious too. Just the overall thought of it blows my mind. He kept saying, “look it up. Look it up. It’s true!” I just wanted to say, “you look it up and show us your proof, because it doesn’t exist!!!” LOL

Reply 2 likes

Avatar of TheDo114
TheDo114

Well-known member

762 messages 1,203 likes

He was DEAD serious too. Just the overall thought of it blows my mind. He kept saying, “look it up. Look it up. It’s true!” I just wanted to say, “you look it up and show us your proof, because it doesn’t exist!!!” LOL

I know you can do it for trailers, but I never heard of this being done for trucks and even less for emission systems.

Reply 3 likes

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