Diesel Exhaust Fluid (DEF) keeps trucks and machinery within federal emission guidelines. It’s a mixture of deionized water and urea that turns harmful nitrous oxide emissions into water and gas, much less harmful. Since 2010, DEF has become essential for companies that use heavy-duty diesel engines in their vehicles and equipment.
Because it’s so important, it’s crucial to understand how bad DEF could affect engines, how to spot bad DEF, and how to prevent it.
Does DEF Go Bad?
DEF only goes bad if contaminated by another material like diesel fuel, antifreeze, windshield washer fluid, dirt, and water. If that happens, the DEF should be disposed of as per the instructions in the SDS sheets and local regulations.
How Long Does DEF Last in Storage?
Unlike with other diesel fuel and chemicals, DEF doesn’t go bad with age. There are some estimates for a shelf life of 12-18 months, though the cooler it’s kept, the longer the shelf life. DEF that hasn’t been contaminated but is beyond the recommended shelf life can be tested with a refractometer to see if the urea content is still within the acceptable range (31/8-33.2% by weight). Even beyond the shelf life, but not contaminated, the product should still be functional. However, most users would dispose of the older DEF due to age concerns whether real or perceived.
How Do You Know DEF is Bad?
The best way to spot bad DEF is by simply looking. DEF is naturally clear so if it looks cloudy or discolored in any way, it’s probably old or contaminated.
Another way to tell if DEF has gone bad is through the performance of your equipment:
- Increased DEF consumption by equipment
- Decreased DEF effectiveness
- Equipment issues or failure
- Component damage
- Selective Catalytic Reduction (SCR) system issues
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Storing DEF in the Summer
Can DEF be stored in sunlight? The answer is no. The more DEF is exposed to heat, the more ammonia it releases, making it unpleasant to work with. People don’t want to be around something that has a strong smell of ammonia. Note that DEF should never be dispensed in a small, confined area no matter its age or quality. Dispense it in a well-ventilated area or outdoor environment.
DEF should be stored in a cool, dry place with the product temperature between 12 to 86 degrees Fahrenheit. You can keep the container in a shaded area or cover it with a canopy or tote cover. Make sure the caps are securely tightened as well.
You can also learn if DEF freezes here.
Hart Fueling has wholesale DEF ready to deliver directly into your vehicles and equipment. We can refill existing containers or replace empty ones. Choose from 2.5-gallon jugs, 55-gallon drums, 275/350 gallon totes, and mini bulk/bulk containers. No matter your need, we can take care of your DEF refueling with convenient scheduling.
Learn more about our DEF delivery options by calling us today!