How to Prevent Diesel Gelling

It took a while this year, but cold temperatures have arrived in most parts of the country. While most of us don’t think twice about the fuel we are putting in our vehicles, fueling with diesel requires more thought. Diesel begins to freeze at a higher temperature than gasoline. As it freezes, it begins to gel. Typically, this can happen anytime the temperature drops below 32 degrees Fahrenheit, but most often when the temperature hits 15 degrees. This diesel gelling process makes it impossible to pump through fuel tanks and can actually shut down equipment or vehicles entirely. Fortunately, even during the colder months of the year, there are ways to prevent diesel gelling.

cold diesel fuel that can gel

What Causes Diesel Gelling

No. 2 fuel diesel (the diesel used in our vehicles) contains a naturally occurring substance called paraffin wax. During warm temperatures (above 32 degrees Fahrenheit), this paraffin wax stays liquid and flows freely through the fuel filters in vehicles. As the temperatures begin to drop, however, paraffin wax begins to crystalize. The colder it gets, the more crystals.

What Temp Does Diesel Gel?

At around 14-15 degrees Fahrenheit, the paraffin wax completely crystalizes, clogging the filter and stopping any fuel from passing through the tank. People in this industry call this instance the Cloud Filter Plugging Point (CFPP). When temperatures cause the diesel to hit CFPP, your vehicle or equipment is not going anywhere, and fuel operations will cease.

How to Keep Your Diesel From Gelling

Because paraffin wax is naturally occurring, there is nothing you can do to change the properties of this substance. There are, however, steps that diesel companies recommend for preventing diesel gelling.

  1. Keep the Vehicle Warm. For all of you living in Florida, Texas, or Southern California, you probably won’t have a problem with diesel gelling. For those living where temperatures consistently drop below freezing multiple times during the year, keeping your vehicle warm is difficult. If you have the option to store your vehicle in a climate-controlled garage, you won’t have to worry about diesel gelling. If you don’t have that option (which, most people don’t), read on for the most popular option.
  2. Add the Additive. Fortunately, there is an additive that diesel companies add to their own fuel tanks and equipment to prevent diesel gelling. Most, if not all, the places you fill up for diesel will also use this additive. You can add it yourself before you fuel up. Before you fill up your tank, add the additive and your filter will be crystal-free for anything under 40 degrees Fahrenheit!
  3. Choose No. 1. The final suggestion is to switch from No. 2 fuel diesel to No. 1 fuel diesel. No. 1 fuel diesel does not have paraffin wax, and therefore, does not gel at any temperature. While no. 1 diesel fuel will cost slightly more at the pump, it may be worth it to ensure your vehicle or equipment runs smoothly during the winter months.

Trust the Experts at Hart Fueling

We are grateful to have a team at Hart with superior fuel expertise. If you are curious about which anti-gel brands are best to use for your specific needs to prevent diesel gelling, do not hesitate to contact us. We would be happy to provide you with suggestions.


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