We’re all new to these cold weather conditions. So, we’ve had an increase in calls related to this extreme weather. Here’s the answer to one of the top questions of the day: Diesels will start to gel in temperatures this low!

In severe cold, even the best winter blend diesel fuel can reach its cloud point (the measure of diesel’s low-temperature operability) and begin to gel up. Due to so many differences in fuel quality existing across North America and the fact that each vehicle’s exposure to cold weather will be different, there is no definitive temperature at which diesel begins to gel. However, most fuels reach their cloud point between 20 degrees F and -18 degrees F. Diesel fuel gels in cold temperatures because it contains paraffin wax, which normally improves fuel viscosity and lubrication. When temperatures begin to fall, this paraffin wax thickens and turns into a cloudy mixture. This is a part of a phenomenon called “diesel fuel gelling,” in which the problem can become so advanced that the paraffin wax can actually clog fuel filters and solidify to the point where the fuel will no longer flow, basically rendering your engine useless. Diesel fuel gelling has the potential to occur when temperatures drop below 32 degrees Fahrenheit, although the exact temperature it happens at will vary from fuel batch to fuel batch.

Gelled diesel: Diesel gelling is when cold temperatures cause diesel fuel to turn from a liquid into a gel-like substance. The diesel fuel solidifies into a waxy or gel-like substance. Fuel is no longer able to be pumped or filtered through the engine.

How do you prevent your diesel fuel from gelling?
Store Vehicle above 32 degrees
Use a Fuel Additive to prevent gelling

We recommend AC Delco Diesel Fuel Additive. You can give us a call at 479-646-8600 to order or make an appointment for us to get that added for you.

If you are currently facing issues with diesel gelling you will need to thaw the frozen lines before you can resume normal driving.

I hope this information helps!

If there is anything vehicle-related, anything from road trips to car shopping to service advice & everything in between, if you have a question you would like me to address please email cathyn@harryrobinson.com. I would love your feedback & to address anything you have questions about.

Thank you all & Stay Safe Yall!
–C