Diesel Exhaust

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DEF Services to Meet Every Need

Maintaining an adequate DEF supply is integral to your business–and Retif can help. We’ll get you set up with on-site storage solutions or DEF delivery as needed. And our bulk pricing options help keep your net profits high.

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Fuel Storage Tanks

Retif offers DEF tanks for your on-site storage needs, and provides delivery and installation. Our equipment maintenance program is also available to keep your tanks clean and your DEF pure.

Learn more about our storage tank rentals.

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Fuel Delivery

Purity of your DEF additives is vital to keep your trucks running for the long haul. Retif provides automatic DEF tank monitoring to make sure you never run out, and on-demand DEF delivery whenever you need it.

We have the DEF delivery schedule to meet your needs.

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Bulk Pricing

Keep your operating costs low with flexible bulk DEF pricing, secured via budget-friendly fuel contracts. Whether you have one truck or 100, we supply the product to keep your fleet on the road all year round.

Learn more about opting into a fuel contract.

More Retif Products
& Services

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Fuel Products

Bobtail, transport, and dockside gas and diesel fuel delivery to commercial businesses across the Southeast.

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Engine oil, greases, and lubricants for your equipment. We supply and deliver in sizes ranging from 5-gallon buckets to bulk totes.

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Diesel Exhaust Fluid (DEF)

DEF delivery, tanks for DEF storage, and transfer & pumping equipment to keep your DEF clean and pure.

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Tank Rentals

For onsite equipment refueling and backup fuel supply. Our fuel storage tank rentals range in size from 650 to 20,000 gallons.

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Fuel Contracts

Whether you are trying to meet a budget, win a bid, or simply spread risk, Retif Oil & Fuel is your fuel contract solution.

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Equipment Maintenance

Routine purification services, oil analysis, oil dehydration & filtration, and consulting & design.

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Fuel & Lubricant Services

Site assessments, fuel futures contracts, and convenience store consulting.

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Fleet Fuel Card

Access to over 57,000 locations nationwide. Instantly track and verify fuel purchases to better manage your fleet fuel usage.

Diesel Exhaust Fluid (DEF) FAQ

What is DEF?

Diesel Exhaust Fluid or “DEF” is an important part of keeping heavy-duty trucks and machinery operating within federal emission guidelines. Starting in 2010, changes in EPA standards required diesel-burning engines to reduce their pollution levels. DEF fluid can help accomplish this. 

What is DEF made of?

DEF is typically made of deionized water and urea. 

What does DEF do?

Using the combination of deionized water and urea DEF helps transform nitrous oxide emissions into water and gas.

How long does DEF last?

The shelf life of DEF is typically about one to two years when stored at a temperature of 75 degrees. In the field, a full DEF tank can last about 63,000 miles, but it can depend on your own driving habits. 

Where can I buy DEF?

DEF can be purchased by visiting our website. For a quote, please reach out to one of our sales representatives at (800) 349-9000 or contact us.

What is DEF used for?

At its most basic level, DEF is used to help keep diesel emissions clean. Starting in 2010, EPA standards started to apply to diesel-burning engines as well. With its combination of deionized water and urea, DEF eliminates nitrous oxide emissions and turns them into water and gas. 

How to dispose of DEF?

If you spill DEF, isolate the spill in a non-combustible material such as sand. Avoid spilling the liquid in a drain. If you do so, rinse out rigorously. If DEF gets on your vehicle, you can wipe it with water. 

DEF Resources

Close up image of an illuminated check engine light on a vehicle's dashboard
Contaminated DEF: Signs and Solutions
As much as we'd like to deny it, mistakes can happen to anyone, and DEF system contamination is always just an accident away. Even experienced drivers and mechanics have found themselves face to face with a contaminated fuel tank... and this kind of incident can send a good truck straight... more
truck driving down highway
Temperature Effect on Diesel Exhaust Fluid
Diesel exhaust fluid, or DEF, is a key component in the selective catalytic reduction, or SCR system for modern diesel engines. DEF breaks down harmful NOx (Nitrous Oxide) emissions that come from a diesel vehicle’s exhaust stream. It also helps keep vehicles’ emissions compliant. DEF is a non-toxic, non-hazardous, and... more
truck driving down the highway
What Does DEF Do?
Back In 2010, the EPA began requiring diesel engines to reduce their production of NOx emissions (i.e. nitrogen oxides) in an effort to reduce air pollution. That reduction was accomplished by using the additive Diesel Exhaust Fluid (DEF). Today, almost all heavy machinery and truck diesel engines utilize DEF to... more