App Download banner
Call Toll Free
Manual Order Form
Show More Entry Fields

Product ID(s) have been added to your cart

Shop More Checkout
2 Step Checkout

Free Shipping! Every Product, Every Day!

You are here: Home > Commercial Truck Supplies > Diesel Exhaust Fluid

Diesel Exhaust Fluid

What is DEF?

Diesel exhaust fluid (DEF) is a non-toxic colorless solution, composed of 32.5% urea and 67.5% deionized water. The fluid gets sprayed into the exhaust stream of diesel vehicles to help meet government-mandated emissions requirements.

View All Products
Ordering in Bulk?
Free Shipping

Why Do Trucks Need DEF?

DEF Breaks Down Emissions

Diesel Exhaust Fluid is mainly used for a process called Selective Catalytic Reduction (SCR), which deteriorates dangerous NOx emissions from diesel engines and turns them into water and nitrogen.

Trucks Don't Run Without DEF

As of 2010, the EPA requires auto manufacturers to put a sensor in vehicles that ensures there's always diesel exhaust fluid available. If your vehicle goes below 10%, your dashboard will begin warning you DEF levels are low. If you're driving an older vehicle that isn't monitored and you run out of Diesel Exhaust Fluid, your vehicle's engine power will be reduced and limited to lower speeds until the DEF tank is replenished.

Improved Gas Mileage

Although many people think DEF brings down a truck's fuel mileage, it actually does the total opposite. Since diesel exhaust fluid removes pollutants from the fuel and prevents gas exhaust recirculation, engines with consistent DEF usage typically see around 5% better fuel economy.

Passing DOT Inspections

The last thing truckers hauling a load want to happen is the Department Of Transportation to flag them for not meeting DEF requirements. Not only will the DOT write the unsuspecting truck driver a ticket, they'll hold their load hostage until the truck meets proper DEF standards, costing drivers time and money.

If you're looking to replenish your truck's diesel exhaust fluid, Keller-Heartt stocks a huge inventory of DEF and numerous DEF equipment for trucks, including everything from electronic pumping systems and tank systems to dispense couplers and adapter kits. If you're a owner/operator of your own semi-truck, we carry cases of UltraPure DEF. Or, if you a manage a larger fleet of company drivers, we offer bulk 55 Gallon Drums and 330 Gallon Totes.

Sort By:
Diesel Fuel Supplement - Case Of 12 (1 QT Containers) Diesel Fuel Supplement - Case Of 6 (80oz Containers) Diesel Fuel Supplement - 55 Gallon Drum Diesel 911 - Case Of 12 (1 QT Containers)
Diesel 911 - Case Of 6 (80 Oz Containers)