A delete kit removes emissions control equipment from your 2018 Ram 2500 diesel engine
A delete kit is a set of parts and modifications that remove or bypass the diesel particulate filter (DPF), selective catalytic reduction (SCR) system, and exhaust gas recirculation (EGR) system from your truck's emissions control setup. These components are designed to reduce harmful pollutants before they leave the tailpipe. When deleted, the truck produces more power and torque, uses less fuel, and requires less maintenance on those specific systems.
For a 2018 Ram 2500 with a 6.7-liter Cummins diesel engine, delete kits typically include a new downpipe, tuning software, and sometimes a new exhaust manifold or intake components, depending on which systems are being removed. The installation usually requires a diesel shop with tuning capability, and the process takes several hours to a full day.
Before you consider this modification, you should understand the legal, financial, and practical consequences. This is not a straightforward bolt-on upgrade — it has real costs and real risks that many truck owners discover only after the work is done.
Key Takeaways
- Delete kits remove emissions equipment that reduces pollution, which is illegal to do on vehicles registered for street use in the United States under the Clean Air Act.
- Federal fines for deleting emissions systems can reach $37,500 per vehicle, and some states add their own penalties on top of that.
- Diesel shops that perform deletes may face fines, loss of licensing, or civil liability if a customer's truck is caught, and some shops have closed because of enforcement actions.
- Deleted trucks often fail state emissions testing, which prevents registration renewal and can result in the truck being declared unregisterable in your state.
- Warranty coverage from Ram and Cummins is typically voided once a delete is discovered, leaving you responsible for all engine repairs.
Federal law and the Clean Air Act make street-use deletes illegal
The Clean Air Act prohibits removing, disabling, or rendering inoperative any emissions control device on a vehicle registered for highway use. This applies to all 50 states. The Environmental Protection Agency (EPA) and the Department of Justice (DOJ) enforce this rule, and they have been actively pursuing both vehicle owners and shops that perform deletes.
The EPA considers a delete kit a "defeat device" — the same category as the software used in the Volkswagen diesel scandal. Even if you never drive the truck on public roads, registration for street use is what triggers the law. Off-road-only vehicles in some states may fall into a different category, but the burden is on you to prove that status, and most states do not have a clear off-road registration class for trucks this size.
Penalties for individuals include civil fines up to $37,500 per vehicle under federal law. Some states, including California, add their own penalties on top of the federal fine. A few states have pursued criminal charges against shop owners, though individual vehicle owners are typically pursued civilly rather than criminally.
State emissions testing will catch a deleted truck
If your state requires emissions testing for vehicle registration — which includes most states east of the Mississippi and several western states — a deleted 2018 Ram 2500 will fail. The test reads the truck's onboard diagnostic system (OBD-II) and checks for the presence and function of emissions equipment. A deleted truck either shows missing components or shows fault codes that indicate the systems have been disabled.
Failing emissions testing prevents you from renewing your registration. Some states will not issue a registration at all until the truck passes. Others allow a one-time waiver or repair period, but that period typically requires you to restore the emissions equipment to pass the next test. A few states have begun flagging deleted trucks in their registration databases, which means the truck cannot be registered even in another state once it is flagged.
If you are caught driving an unregistered vehicle, you face fines, impoundment, and potential criminal charges depending on your state. The truck itself can be declared unregisterable, meaning it cannot legally be driven on any public road in that state.
Diesel shops performing deletes face increasing enforcement
The EPA and state environmental agencies have been targeting shops that perform deletes. Enforcement actions have included civil penalties, criminal charges against shop owners, and loss of business licenses. Several well-known diesel shops across the country have closed or stopped offering delete services after facing fines or legal action.
A shop that performs a delete on your truck may be liable if you are caught, and some customers have found themselves in disputes with shops over who bears the cost of the fine or the cost of restoration. Shops that advertise deletes openly are more likely to be targeted, while those that perform them quietly still face risk if a customer's truck is inspected.
If you are considering a delete, ask the shop directly about their liability insurance and what happens if your truck is caught. Many shops will not put the delete in writing, which creates a problem if you need to prove the work was done by them and not by you.
Warranty coverage is voided once a delete is discovered
Ram and Cummins both void warranty coverage on any engine or emissions-related component once a delete is discovered. This includes the engine itself, the transmission, and any related systems. The warranty void is permanent — you cannot restore it by reinstalling the original equipment.
If your engine fails after a delete, you are responsible for the full cost of repair or replacement. A Cummins 6.7-liter engine rebuild can cost $4,000 to $8,000 depending on the damage, and a full replacement can exceed $10,000. Transmission repairs, which are sometimes needed after a delete because of changed engine characteristics, are also your responsibility.
Some owners have attempted to hide a delete by reinstalling original equipment before taking the truck to a dealer, but dealers can detect this through service records, diagnostic codes, and physical inspection. Once detected, the warranty is still voided retroactively.
Performance gains come with trade-offs in reliability and resale value
A deleted 2018 Ram 2500 typically gains 50 to 100 horsepower and 100 to 150 pound-feet of torque, depending on the tuning and which systems are deleted. Fuel economy may improve by 2 to 4 miles per gallon under certain driving conditions. Maintenance costs on the deleted systems themselves drop because you are no longer regenerating the DPF or replacing SCR fluid.
However, the increased power and torque put more stress on the transmission, driveline, and suspension. Transmission failures are more common in deleted trucks, especially if the truck is towing or driven aggressively. Some owners report increased engine noise and a rougher idle after a delete.
Resale value is significantly affected. A deleted truck is worth less than an original truck to most buyers because of the legal and warranty issues. Private buyers who want a deleted truck may pay a small premium for the performance, but dealers will not accept a deleted truck as a trade-in, and banks may refuse to finance one. If you ever need to sell, you will have a harder time finding a buyer and will likely take a loss compared to an unmodified truck.
Restoration to original emissions equipment is possible but expensive
If you decide to restore your truck to original emissions equipment, the cost depends on how much was deleted. A full restoration — replacing the DPF, SCR system, EGR cooler, and all associated piping and tuning — typically costs $2,000 to $4,000 in parts and labor. You will also need to have the engine tuned back to stock, which adds another $500 to $1,000.
Restoration does not automatically restore your warranty. Ram and Cummins will evaluate the truck to determine if the delete caused any damage before deciding whether to cover repairs. If the engine or transmission was damaged by the delete, those repairs are still your responsibility even after restoration.
Some states allow a one-time restoration period before revoking registration, but this varies. Check with your state's environmental agency or your local emissions testing facility to understand what your state requires before you invest in restoration.
Frequently Asked Questions
Can I delete my 2018 Ram 2500 if I only drive it off-road?
The Clean Air Act applies to any vehicle registered for street use, regardless of how you actually drive it. If your truck is registered for highway use, a delete is illegal. Some states have off-road-only registration classes, but they typically explore to vehicles that cannot legally be driven on public roads at all. You would need to verify with your state's motor vehicle department whether your truck qualifies.
What happens if I get caught with a deleted truck?
You face a federal civil fine up to $37,500, plus any state penalties. Your truck will fail emissions testing and cannot be registered. You may be required to restore the emissions equipment at your own expense before the truck can be registered again. Some states have begun pursuing criminal charges against repeat offenders.
Will a deleted truck pass a visual inspection at a diesel shop?
A physical inspection by a trained technician will reveal a delete because the DPF, SCR system, and associated components are visibly missing or modified. Diagnostic scanning will also show fault codes or missing system data. A delete cannot be hidden from a professional inspection.
Can I restore a deleted truck and get my warranty back?
Restoring the original equipment does not automatically restore your warranty. Ram and Cummins will inspect the truck to determine if the delete caused damage. If damage is found, those repairs are your responsibility. Even if no damage is found, the warranty may not be fully restored depending on the manufacturer's policy.
How much does a delete kit cost, and is it worth it?
A delete kit typically costs $1,500 to $3,000 in parts, plus $500 to $1,500 in labor, depending on the shop and which systems are deleted. The performance gains are real, but they come with legal risk, warranty loss, and potential transmission damage. For most owners, the long-term costs and risks outweigh the short-term performance benefit.