How to Handle Diesel Exhaust Fluid During the Winter

When winter approaches, understandably, you may be worried about the repercussions of your Diesel Exhaust Fluid (DEF) freezing. However, we are here to say: don’t.

It Will Happen

Commercial DEF contains 67.5% deionized water and 32.5% purified urea, allowing it to have the lowest possible freezing point (12 degrees Fahrenheit and -11 degrees Celcius).

Having said that, it will still happen when the temperatures fall below those temperatures. Like water, it will turn to slush, then reach a solid state.

However, you should not panic. DEF freezing will have no impact on the start-up or functionality of your vehicle.

Luckily, most aftertreatment systems feature a tank heater that defrosts DEF when the vehicle is running. DEF is reusable once it is thawed out.

Make Room for Expansion

Like water, DEF accumulates more space when it turns from slush to solid. Do not fill the tank completely full as DEF can expand up to 7% when frozen.

By filling the tank, your storage reservoir runs the risk of cracking and breaking which can be a costly fix.

As mentioned above, DEF will thaw out and be functional after the vehicle has been started.

Ditch the Additives

Adding any other fluids to prevent freezing is highly recommended against as this will prevent the DEF from properly functioning.

DEF is able to sustain and function through the freezing period, and contaminated fluid may result in costly repairs to your aftertreatment system.

Proper Storage

On average, DEF has a shelf life of 12 months.

However, utilizing the proper storage methods will help prolong the storage life of your DEF. This fluid should be kept indoors to put off freezing as long as possible.

The urea is highly susceptible to sunlight and higher temperatures as well so DEF should remain indoors, even in warmer months.

Along with being indoors, your DEF should be kept in HDPE plastic or stainless steal as it is mildly corrosive. Make sure that the tank and container seals remain intact to remain free from dirt and dust.

Check Quality

Your DEF is equipped with sensory detecting triggers that continually inspect the quality of fluid being used. You will receive a code fault if the sensor detects an imbalance within the fluid.

When this happens, your DEF may be experiencing a higher percentage of water from different elements, including condensation and rain water.

It is important to be familiar with these codes as they ensure DEF is running properly.

DEF must be kept free from excess water and contamination.

Have you experienced freezing within your Diesel Exhaust Fluid during the wintertime? Comment below to share some of your tricks!

Be Mindful of Filter Cartridge

DEF is inserted by being injecting into the exhaust stream with a specialized dosing module where the water from the fluid begins to vaporize.

When the injectors are damaged, DEF can cause trouble within the engine. You may experience the injector tips exploding or leave your engine cooling.

Your aftertreatment system should feature a cartridge filter that protects your DEF injection.

Check to ensure you are injecting your DEF properly.