What is Def Delete Kit - 5 Usage Tips for Beginners

The Def Delete Kit: Restore Your Diesel Engine

So your old diesel truck has been running rough lately and the check engine light came on again. Uh oh, sounds like it could be a problem with the DEF system this time. Diesel exhaust fluid, or DEF, is that blue liquid you have to refill to meet emissions standards. If the DEF injector or sensor went bad, you’re looking at an expensive repair bill to get your truck back on the road.

But don’t panic just yet. For a fraction of the cost of a shop repair, you can pick up a DEF delete kit and handle this yourself in your own garage. A delete kit will bypass the troublesome DEF components so you can disable the system and get your truck running right again. No more warning lights, no more costly sensor replacements, and no more filling up that DEF tank every few thousand miles. A delete kit is an easy, affordable solution to free your diesel engine from the constraints of emissions controls. In just a few hours, you’ll be driving with confidence again knowing your truck’s DEF woes are a thing of the past.

What Is the Def Delete Kit?

A def delete kit is designed to remove built-up diesel exhaust fluid (DEF) deposits and restore your diesel engine to like-new condition.

DEF is used to reduce nitrogen oxide emissions in many modern diesel vehicles, but over time it can build up in your engine and emissions system. This buildup reduces engine power and performance. A def delete kit cleans your entire DEF system, including:


The DEF injectors spray DEF into your exhaust to neutralize emissions. Buildup here reduces spray effectiveness and engine power. A def delete kit will clean your DEF injectors to restore full spray functionality.

Pumps and Lines

DEF pumps and lines carry DEF from the tank to the injectors. Gunk and residue in these components reduce DEF flow, hurting engine performance. A def delete kit flushes your DEF pumps, lines and other components to allow maximum DEF flow.


DEF level and temperature sensors monitor DEF levels and ensure proper DEF temperature for maximum effectiveness. Buildup on sensors provides inaccurate readings to your vehicle’s computer, reducing power. A def delete kit cleans all DEF sensors to restore accurate monitoring.


Over time, DEF residue and sludge accumulate in your DEF tank. A def delete kit cleans and decontaminates your DEF tank to prevent clogs and keep DEF pure.

A def delete kit provides a total DEF system refresh for peak diesel engine power and performance. All you need to do is pour in the solution, run your engine, and drive like new!

How the Def Delete Kit Restores Your Diesel Engine

A def delete kit cleans up the diesel exhaust fluid (DEF) system in your vehicle and gets it running like new.

DEF is what reduces the nitrogen oxide emissions from your diesel engine. Over time, the DEF injectors and lines can get clogged up with crystallized urea and other contaminants, hurting performance and fuel economy.A def delete kit fixes this by:

  1. Flushing out the entire DEF system with a special cleaning fluid. This dissolves any built-up deposits and gunk clogging injectors, pumps, sensors and hoses.
  2. Replacing old, worn out parts like DEF injectors, pressure lines, sensors and control modules. New, high-quality components help ensure proper DEF delivery and optimal emissions system function.
  3. Providing a preventative treatment you add to your DEF tank. These additives help prevent future crystal buildup and keep your DEF system clean.

With a freshly cleaned and restored DEF system, your diesel will run better than before. You’ll notice improved acceleration, higher MPGs, reduced emissions system warnings and a smoother, quieter ride. Best of all, a def delete kit is easy to install yourself, saving you money versus paying a shop to do the work.

If your diesel’s performance and fuel economy have taken a hit lately, a def delete kit could be just what the doctor ordered to get you back on the road and running like a champ. Why put up with a subpar system when an affordable fix is within your reach? A clean, well-maintained DEF system means happy motoring.

Where to Buy the Def Delete Kit

If you’re looking to restore performance and fuel economy in your diesel engine, a DEF delete kit is a great solution. DEF (Diesel Exhaust Fluid) is required in many modern diesel engines to meet emissions standards, but it can be problematic and reduce engine power. A DEF delete kit will bypass your truck’s DEF system so you can remove the entire apparatus.

Where to Purchase

You have a few options for purchasing a DEF delete kit:

  • Specialty diesel parts stores: Stores that specialize in diesel performance parts and upgrades will likely carry DEF delete kits. They may even offer kits that are vehicle-specific. These kits will come with detailed instructions for uninstalling your DEF system.
  • Online retailers: Websites like DieselSite, Sinister Diesel, and Diesel Ops are popular for purchasing DEF delete kits and other diesel performance upgrades. They have a wide selection with options for most makes, models, and years of diesel trucks. While they may have good prices, you’ll have to wait for the kit to ship and installation instructions may be more generic.
  • Local diesel mechanic shops: Some diesel repair shops that specialize in performance upgrades and modifications will sell and install DEF delete kits. Going through a shop means they can uninstall your DEF system for you and ensure it’s done properly. However, their prices may be higher than if you did the work yourself.
  • Custom fabrication: For some older or less common diesel trucks, you may need to have a DEF delete kit custom fabricated. Check with local fabrication and machine shops to see if they can manufacture a kit to your vehicle’s specifications. Custom kits will likely be the most expensive option but will provide the best fit.

Whichever route you choose, be aware that removing your DEF system may not be legal for on-road use in some areas due to emissions regulations. Make sure you understand all federal, state, and local regulations regarding DEF delete kits before purchasing and installing one.


So there you have it, everything you need to know about def delete kits and how they can help restore lost performance and fuel economy in your diesel engine. For a few hundred bucks and a couple hours of your time, you’ll be back on the road with an engine running as strong and clean as the day you bought it. Pretty sweet deal if you ask me. If your diesel has been feeling down on power or guzzling more fuel than usual, do yourself and your wallet a favor and pick up one of these kits. Your engine will thank you, and so will your bank account the next time you fuel up. Time to get deleting!