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Best Practices

Tips for DEF Maintenance in Winter

ASC BestPractices Index V1

Tips for DEF Maintenance in Winter

When the temperatures drop, it’s important to take extra care with your diesel exhaust fluid (DEF). DEF has a freezing point of about 12 degrees Fahrenheit and can cause your engine to derate or become damaged if you operate your equipment with frozen fluid. To help keep your machine running at its best, follow these tips and best practices for DEF maintenance in winter.

Warm up your engine before working
A crucial first step for diesel exhaust fluid maintenance in winter is warming up your equipment. By running the engine for a few minutes prior to beginning work, you can thaw out any frozen DEF.

Watch out for engine fault codes
Most modern pieces of equipment have telematic systems that display faults when the DEF is frozen. If you notice this fault code, do not work with your machine until the diesel exhaust fluid has thawed and the fault goes away.

Don’t completely fill your diesel exhaust fluid tank
A key tip for DEF maintenance in winter is to not fill your tanks all the way up. The fluid will expand up to 7% if it freezes, which can crack the tank if it’s completely full.

Check expiration dates
Most types of DEF have a shelf life of about one year. If you are using fluid from the previous season, look at the expiration date before adding it to your equipment.

Store DEF properly
Diesel exhaust fluid containers may burst if your DEF freezes and expands. To keep that from happening, we recommended storing it in a well insulated or temperature controlled area to protect your fluid from the worst of the winter cold. Always store it between 12℉ and 86℉ to prevent freezing and early degradation.

Drain the tanks before storing
When you store your heavy equipment for the season, it’s critical that you drain your diesel exhaust fluid tank to prevent machine damage. When it’s time to work again in the spring, flush the DEF system with distilled water before adding new fluid.

If you have any questions about DEF maintenance or diesel exhaust fluid in general, contact our team today.