Diesel Exhaust Fluid (DEF) is a solution of urea and water that's injected into the exhaust stream of diesel vehicles to turn NOx gases (harmful emissions) into nitrogen and water. This system is called a Selective Catalytic Reduction (SCR) implemented by vehicle manufacturers to meet EPA emissions standards in 2010.

What happens when you run out of DEF?

The Cost of Running Out of DEF‍

In a best-case scenario, running out of DEF simply means refilling the tank and restarting your machine. If you have DEF nearby, you could be back to work within minutes. But sometimes it isn't so quick and easy.

How often do you put DEF in a diesel?

The DEF tank needs to be filled once for every 3 to 4 times that you refuel with diesel fuel.

Do all diesel engines require DEF?

A: Because almost all diesel-powered passenger cars and trucks built since 2010 are equipped with Selective Catalytic Reduction (SCR) and require Diesel Exhaust Fluid (DEF), it is readily available at most fueling stations and automotive parts retail stores.

Can a diesel engine run without DEF?

If you ignore the DEF warning the truck will cease to work. Some diesel engine manufacturers allow the engine to go into reduced power mode so the truck can “limp home” or limit the number of times you can turn the engine over. At some point though the diesel engine will not start.

Diesel Exhaust Fluid (DEF) - How it works.

Can I use water instead of DEF?

Subject: RE: Anyone replace DEF with water? Water won't hurt the system but it will de-rate you pretty quick. ECM compares NOx values pre/post, if conversion is low it will start throwing codes and will eventually derate.

Can you delete the DEF system?

Deleting your DEF system can help save you money. Plus, your exhaust might have a bit of a beefier growl once you're done. DPFs are completely different. Also known as diesel particulate filters, these little buggers are exhaust filters installed in-line on your exhaust system.

Can I pee in DEF tank?

The urea found in urine is not in the proper concentration needed for DEF, nor is it of a sufficient level of purity, in either urea or water. The bottom line, to spell it out just one more time… urine and DEF = Never. DON'T PEE IN YOUR DEF TANK!

Is it illegal to delete DEF?

There is no way around this; it is 100% illegal to tamper with or modify the emission system on your truck in any way. It isn't a state or local law (although those exist, as well), but Federal law.

How long does DEF fluid last?

The American Petroleum Institute recommends that you determine when DEF was put in the vehicle. The storage life of DEF is about 12 months in optimal conditions. If DEF has been stored in the vehicle over the past 12 months, it is recommended that it be drained and replaced.

How do I know if I need to add DEF fluid?

DEF is consumed at a rate of about 2-3% relative to the amount of fuel you are using. This means between 1.2 and 2.0 gallons of DEF will be required for a vehicle with a 65-gallon gas tank. If you have a five-gallon DEF tank, DEF should be replaced every third or fourth time you fill up.

How many miles does a tank of DEF last?

Most DEF tanks require one gallon of DEF for every 50 gallons of diesel fuel, and one gallon will generally last between 300 to 500 miles.

Does Walmart have DEF?

DEF Diesel Exhaust Fluid - (2) 2.5 Gallon - Walmart.com.

How often should you change a DEF filter?

To prevent these problems from occurring, UREA/DEF filters must be replaced every year or between 120-150,000 miles.

What is a substitute for DEF fluid?

DEF is urea or otherwise known as aqueous ammonia. Windshield washer fluid that contains ammonia will do in a pinch.

Is deleting a diesel worth it?

To put it bluntly, no, you should not remove the emissions equipment from any diesel pickup. Regardless of local and state testing requirements, it is a federal crime to remove any factory installed emissions equipment. Removing emissions equipment also voids the vehicle's factory warranty.

How much is a DEF delete?

How Much Does A DPF Delete Cost? Prices and service times vary on the type and year of the unit and the extent of the delete but roughly range from about $3000 to $10,000. This cost is often either the same or less expensive than replacing the after-treatment systems upon failure.

In what states is illegal to delete diesel?

The states are California, New York, Massachusetts, North Carolina, Connecticut, Hawaii, Maine, New Jersey, New Mexico, Oregon, Washington State, and Rhode Island.

How many gallons does a DEF tank hold?

DEF tanks will hold between 15 and 50 gallons, depending on the equipment size and horsepower.

Is Blue def cow urine?

Diesel exhaust fluid sold in stores and at semi-truck pumps at truck stops in the U.S. does not contain urea derived from cows, bats, or any other animal's urine, and to be clear, diesel owners should under no circumstances urinate in their DEF tanks.

Can you pour DEF down the drain?

Bad DEF should be disposed of immediately and ethically. Do not pour down a drain or dump it outside. Check with your local government and environmental agency to learn how to properly dispose of DEF.

Can DEF system be bypassed?

If you're thinking of bypassing any of your diesel's emission controls, remember that that it's highly illegal and the fines can be steep. The chances of getting caught may be low, but the consequences are costly.

How much does it cost to delete DEF on Duramax?

Deleting the LML DPF requires a delete kit and a tuner. Delete kits run from $300 for a base kit to up to $1,000 if you want to replace the full exhaust system. Adding a tuner is going to add another $700-$1,500 to the price tag.

When did they start putting DEF in trucks?

For years, truck drivers and fleet managers didn't have to worry about smog-proof equipment on their vehicles. Come 2008, the EPA mandated that all three-quarter-ton and larger trucks had diesel particulate filters installed.