Delete kits are popular aftermarket performance upgrades for diesel engines. They often improve fuel economy and performance by removing certain factory-installed components. If you have a PACCAR engine in your truck like I do, you may be wondering if you can delete these components.
Generally, kits are available that can help you delete certain performance-limiting components of your PACCAR engine. Some of the most popular deletions include DPF, DEF, and EGR deletes. However, this should only be done for private and off-highway driving purposes. Otherwise, you could face penalties.
Below, I’ll discuss more information on the different types of deletions, as well as how they can help you improve your truck’s performance.
What Does Deleting an Engine Mean?
Since the exhaust that comes out of diesel engines tends to be quite dirty and oily, it can clog parts of the exhaust gas recirculation (EGR) system over time. This leads to lower fuel economy and performance issues, and often eventually requires either cleaning or replacement, which I know can be quite expensive.
Instead of dealing with all the issues these pollution control components can cause, some diesel engine owners choose to “delete” them.
Despite how it sounds, deleting an engine does not mean removing it. Instead, “deleting” refers to removing certain factory-installed components inside a diesel engine that tend to decrease fuel economy and hinder overall performance.
Different Types of PACCAR Diesel Engine Deletes
There are many different types of diesel engine deletes, but in this article, I’ll be discussing three of the most popular.
These include:
- DPF delete
- EGR delete
- SCR DEF delete
Let’s get into each of these below.
What is a DPF Delete?
The first type of engine delete we will be going over is the DPF delete.
DPF stands for “Diesel Particulate Filter.” A diesel particulate filter is a part of a diesel engine intended to help remove soot to prevent clogging.
Instead of immediately releasing it from the exhaust pipe, a DPF stores this soot inside a canister that contains honeycomb-like compartments. Once all these compartments are full, the exhaust system will begin a “regen cycle” where it uses the fuel in the engine to burn the soot off and push it out through the exhaust pipe.
This process can significantly reduce not only the fuel economy, but the engine power and lifespan in general. Once you remove the DPF, you may notice an improvement in fuel economy by up to 30%!
What is an EGR Delete?
Now, let’s get into what an EGR Delete is.
The Exhaust Gas Recirculation, or EGR, system in a diesel engine reduces the overall exhaust emissions. It uses an electronically-controlled valve, allowing small amounts of exhaust to mix with the air intake system to reduce nitrogen oxide emissions.
While this limits the amount of exhaust that’s released into the air, it also increases the amount of soot in the engine. This, in turn, reduces your fuel economy and can limit your engine’s performance.
It can also cause further damage to your engine, including problems such as:
- Sticky valves
- Cracked parts
- Coolant issues
- Leaky cylinders
Deleting the EGR system will reduce the chances of all of these problems occurring. In addition, it can help your vehicle run cooler to increase its lifespan.
What is an SCR & DEF Delete?
Lastly, we will go over the SCR and DEF delete method.
The Diesel Engine Fluid (DEF) system operates in a similar way to the DPF system. It removes soot from the exhaust system and stores it in a canister, then cleans itself out through a regen cycle.
In addition to the usual problems regarding performance and fuel economy, the DEF can also cause issues related to freezing. The system is made up of mostly water, so you risk having your fuel freeze if you live in a colder climate.
A SCR and DEF delete will take care of all these issues. You won’t have to worry about any of the issues related to performance or freezing again.
Are Diesel Engine Deletes Legal?
Federal law prevents you from modifying the emissions system unless you have the truck re-certified by the manufacturer afterward. They will also need to give you a new emissions label and certification to prove everything was done legally.
Tampering with the emissions system on your truck in any way is not exactly legal. It’s especially illegal if your vehicle is registered or certified for highway use.
If you do delete part of your engine’s emission system, you won’t be able to drive your truck on the highway. Deletions can only be performed on vehicles used for closed-course racing and other private events or off-highway driving. If you get caught breaking any laws regarding emissions equipment, you may be subject to fines and other penalties.
Final Thoughts
Most diesel engines can have certain emissions components deleted, and PACCAR engines are no different. However, before purchasing a delete kit, make sure you’re doing everything legally. Check all the local, state, and federal laws surrounding engine deletes as soon as you begin considering it.
