Will a Deleted Truck Pass Inspection?

Nowadays, DEF comes as a standard for most newer trucks. The system is designed to work in conjunction with the factory SCR system to break down exhaust fumes and clean them before they exit the exhaust system. The catch with this system is that you have to keep the fluid-filled regularly so it functions properly. This is why most users opt to delete their trucks. 

It is possible for a deleted truck to pass inspection. For that to happen, there are some tricks you will need to apply. You can pass the emissions with a deleted diesel by tuning with an OBD scanner, swapping emissions equipment during testing, and controlling the smoke density. That way, your truck will pass emissions. 

This article shows how you can pass the emissions test if you have a deleted truck.

Why Do Drivers Delete the Diesel?

The DEF system is installed in most trucks to prevent emissions of harmful gases into the environment. However, for this system to keep functioning properly, the fluid reservoir must be kept filled regularly. This not only takes time, but it costs money too.

This forces many drivers to delete the system to save money. Many also find that a deleted truck has an increased fuel economy and overall efficiency. The main problem that arises is that doing so is illegal, and there is often an inspection to check for compliance with the emissions regulation. 

Will a Deleted Truck Pass Inspection?

will a deleted truck pass inspection

Nowadays, many trucks are required by law to install DEF and DPF in their engine systems. This is in a bid to reduce harmful truck emissions. Newly manufactured vehicles come with systems already installed. 

However, the practice of deleting diesel has become common, albeit illegal in many regions of the world. Many users still do it since maintaining the system and frequently re-filling the DEF is a hassle.

Many agree that deleting diesel increases the engine’s power and fuel economy. Unfortunately, these users have to contend with the emissions law and the inspection on the same. Here’s how you can pass the inspection with a deleted diesel. 

Tuning with OBD Scanner 

Typically, the computer in your vehicle will show that some parts are missing when you remove the emission equipment. Using an OBD ii scanner will help you find the missing components. The best way to handle the situation is by tuning your car.

Vehicle tuning is basically the modification of your car to increase speed, responsiveness, and overall efficiency. Once you perform the tuning, you need not worry about error codes being displayed on your computer. It is advisable to take your truck to a mechanic with more experience in tuning trucks. 

Swapping Emissions Equipment During Testing

Unfortunately for many. The new and modern emissions testing system is ingenious and makes passing the emissions test very difficult. Therefore, by swapping the emission components during the test will guarantee to pass the test. You can remove them later. 

Controlling Smoke Density

At no point should your vehicle’s smoke opacity exceed 20%. This capacity can only be achieved by tuning. That way, you are unlikely to be stopped by traffic police if your vehicle emits less than 20% dense smoke. 

Driving in a State Where DPF Deletion Is Legal

Alternatively, you can spare yourself all the hassle by driving in a state where DPF deletion is allowed. There are some states that do not have any restrictions on deleted diesel. Here, you can drive the deleted diesel vehicle without worrying about being stopped by traffic police or not passing the inspection.

Therefore, you can choose states without any legal issues. It is important to note that some states require emissions tests for gasoline vehicles, and not diesel. 


DPF deletion is illegal in many regions. This means that you will face legal issues when you drive a deleted vehicle, and this often means a fine. The EPA has the authority to fine you if you are caught driving a vehicle with deleted DPF. The amount of fine tends to range between $2500 to $37500. 

Yes, there are some categories of vehicles that are exempted from the DEF. Some of these significant vehicles include firefighting vehicles, disaster relief vehicles, snowmobiles, hauled vehicles, aircraft refueling vehicles, and special equipment vehicles. 

The Environmental Protection Agency EPA illegalized deleting a diesel truck as it causes harm to the environment. Deleted trucks cause serious pollution. 


To delete or not to delete diesel has been a long-standing debate. Some users claim that deleting it boosts fuel economy and enhances engine performance.

The arguments go on and on, but when all is said and done, DPF is important as it contributes to keeping the environment from harmful vehicle emissions. If you have already deleted your diesel, no need to worry. You can follow the steps outlined above to pass any emissions tests.