What Is a DEF Tank on a Semi Truck?

A DEF tank is an essential component of a semi truck today. It helps to reduce emissions and improve fuel economy, and is a necessary component for any truck driver who wants to stay compliant with the EPA Clean Air Act.

DEF stands for Diesel Exhaust Fluid, which is a mixture of urea and de-ionized water. This fluid is put into the exhaust system of a diesel engine in order to break down oxides of nitrogen (NOx) into harmless nitrogen and water vapor. This process helps reduce air pollution and provides several benefits to both truck drivers and the environment.

The DEF tank on a semi truck is typically located near the fuel tank, usually on the driver’s side. It’s usually made out of plastic or metal and holds up to 15 gallons of DEF fluid. The DEF tank needs to be filled up every time the truck driver stops for fuel, as it gradually gets used up while the engine is running.

To fill the DEF tank on a semi truck, you need to use a special nozzle that connects directly to the DEF tank. The nozzle has two parts: one that screws onto the neck of the DEF tank, and another that attaches to your hose from your DEF supply container. To fill it up, you simply unscrew the cap from your DEF tank, connect your nozzle, then turn on your hose until it’s full.

Maintenance

It’s important to keep your DEF tank clean at all times in order to prevent build-up from occurring inside it. Build-up can cause clogs in your exhaust system which can lead to costly repairs or worse damage if not taken care of regularly.

You should also check your levels often; most trucks come with an indicator light that will tell you when you’re running low on fluid. If you find yourself running low more often than usual or if you’re having trouble filling it up correctly, then there may be something wrong with either your nozzle or with your DEF tank itself.

Conclusion

A DEF Tank on a Semi Truck is an essential component for any truck driver who wants to comply with EPA regulations and improve air quality across America. It holds Diesel Exhaust Fluid which helps break down harmful emissions into harmless nitrogen and water vapor when put through an exhaust system. It needs regular maintenance in order for it to work properly as well as regular refills when needed.

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Susan Delgado