How to Blend No. 1 Diesel With Diesel Fuel for Cold Weather

by Contributor

No. 1 and No. 2 diesel fuels are made for use in highway vehicles. While No. 2 diesel is the more common of the two, No. 1 diesel is better for use in cold weather. This is because it has a lower boiling point and is lighter than No. 2 diesel. This makes it less susceptible to gelling or waxing in cold weather, and thus better able to flow through a car's engine. However, No. 1 diesel is more expensive than No. 2 diesel. This is why many people blend the two diesels together for use in cold weather conditions.

Replace 10 percent of your No. 2 fuel with No. 1 fuel for every 5 degrees of improvement you want in your cold filter plug point (CFPP). The CFPP is the point at which your fuel will start to form wax crystals, which will clog your fuel injectors and engine.

Use kerosene as a substitute for No. 1 diesel fuel if you're not using ultra-low sulfur diesel. Kerosene is a bit less expensive than No. 1 diesel and will blend with your No. 2 diesel just as well.

Buy a No. 2 diesel with an additive blend for improving cold weather performance. This will save you the trouble of having to blend diesels yourself. After all, diesel fuel doesn't smell good, and there's always the risk of spilling it on your clothes.

Let your car run for 10 to 15 minutes before driving it in cold weather. You should do this even if you've put together a No. 1 and No. 2 diesel blend in the engine. Letting your car run for a bit allows the fuel to fully liquefy and become smooth-flowing, which will result in better performance and efficiency.

Buy only as much No. 1 diesel fuel as you think you'll need for two tanks. After all, it's expensive, and the weather might warm up unexpectedly, leaving you with unused diesel in your garage. Two tanks' worth of diesel will allow you to fill your tank and have one tank's worth in reserve. If the weather stays cold, you can always go out and buy some more.

Tip

  • check If you're using ultra-low sulfur No. 2 diesel in your car, you should only blend it with ultra-low sulfur No. 1 diesel in cold weather. Doing otherwise could cause your car to smoke heavily and produce more emissions. It could also damage your car's engine.

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