EPA Says Diesel Deletes Are Still Illegal—What Truck Owners Need to Know Now

Is a diesel delete still illegal for trucks? What is this feature, and why would truck owners want to use it? What did the EPA do about diesel-truck emissions?

Think rolling back climate rules means your diesel delete is suddenly legal? Think again. EPA’s new chief just confirmed that emissions tampering is still being prosecuted, with fines reaching thousands per violation. Here’s what every truck owner and tuner shop needs to understand about the law, the risks, and why federal enforcement isn’t going anywhere despite broader regulatory changes.

Deregulation didn’t go that far

Despite recent EPA guidelines that allow for softened fuel mileage requirements, enforcement of emissions equipment is still in effect for diesel trucks. The EPA has reiterated the regulation that emissions tampering is illegal, and there could be emissions system tampering penalties for anyone caught doing so. These truck emissions violations mean the EPA and current administration haven’t gone back to the days before emissions regulations were put in place, which would mean rolling things back to the early 1970s. Despite the popularity of modifying a diesel truck to improve the truck’s performance, it’s still illegal under Federal law.

Deregulation Day didn’t change diesel delete to no longer be illegal

The EPA announced a “Deregulation Day” on which the most federal regulations were rolled back in the agency’s history. On this day, there were 31 directives issued that created rolling back regulations that impacted many vehicles. The item that got the attention of diesel truck owners was nothing more than a hope and a dream for them to be able to remove diesel emissions equipment. That mandate is the Car GHG Rules, which are for greenhouse gas emissions enacted under President Joe Biden, involving mostly a movement forward for electric vehicles.

What do the Car GHG Rules state?

Without going into all of the specific language, the rules put in place meant stricter greenhouse gas emissions regulations starting in 2027 and lasting through 2032. This could have caused many diesel trucks to be deleted from the market because of the emissions expelled by them. During the deregulation, or rolling back, of these rules, the EPA loosened the reins, and those emissions regulations were no longer going to impact vehicles going forward. This has led to many automakers moving back to larger gas-powered engines, but diesel engines weren’t specifically impacted.

Why are diesel delete packages illegal?

Diesel delete refers to the removal of diesel emissions equipment, which is required to be included in every diesel-powered vehicle produced over the past 20 years. These emissions-reducing items impact the fuel efficiency of the vehicle and require owners to pay more for vehicle service. It is illegal to remove or tamper with the emissions equipment, and a driver with a diesel delete could face serious fines. During the Biden administration, the EPA stepped up enforcement efforts that led to fines for companies producing emissions equipment removal kits for diesel vehicles. Many diesel truck owners hoped the deregulation of emissions requirements would benefit them, but that’s not the case.

The EPA is reviewing diesel tuning laws; sort of

The “Clean Trucks Plan” is a problematic piece of legislation that makes it much more difficult for heavy-duty trucks to handle the larger jobs they are made for. For the most part, diesel-powered heavy-duty trucks haven’t been the subject of any legislation, but that was the next focus during the Clean Trucks Plan. This plan was meant to be a three-year plan to reduce emissions and move commercial fleets from diesel engines to battery electric powertrains. This plan was put in place in 2021, but as you can see, it didn’t make it to fruition during the three-year timeframe.

Texas checks air quality

A diesel delete package is illegal, and diesel engines produce more harmful emissions than gas-powered vehicles. Even after the EPA deregulations, Texas added air quality check stations around San Antonio and Bexar County. These checks are to verify that trucks meet air quality standards, but currently, motorcycles and diesel trucks are excluded from the testing program. The testing program will check gas-powered vehicles between two and 24 years old in the county, helping to improve the air quality around the large city. This could be the middle ground required to avoid smog problems around large cities.

It’s still illegal to install a diesel emissions delete system on your diesel-powered truck. Avoid the challenges of fines and problems with these systems. The EPA rolled back some regulations, but not those involving the emissions associated with diesel-powered trucks.