Key Differences Between Winter Diesel Fuel and Summer Diesel Fuel

When it comes to using diesel fuel, Canada is classified as the country with an "arctic" climate. Temperatures in the winter easily drop to – 40 °C. When such freezing temperatures hit, failing to prep your diesel engine could mean its failure.

At the fuel station, you can choose between "summer" diesel fuel, which is usually suitable for use between May and October, and "winter" diesel fuel, which is good between November and April.

As the summer fuel faces low temperatures, it starts to thicken up. Gelled fuel is useless for your vehicle. That's where the winter diesel blend comes in.

Let's look at the difference between summer and winter diesel fuel options.

Summer Diesel Fuel (Grade No.2)

During warmer months, it's reasonable to use grade no.2 diesel fuel, also called "summer" diesel fuel. It starts clouding at about – 7 °C compared to "straight-up" grade no.1 fuel, which does the same at – 40 °C.

Winter Diesel Fuel (Grade No.1 + Grade No.2)

Winter diesel fuel is a mix of grade no.1 and grade no.2 fuel. The main component of grade no.1 diesel is kerosene. Meanwhile, it doesn't contain paraffin. These two factors lower the cloud and pour points of the mix, thus preventing gelling in cold temperatures.

Depending on the area you live in, the ratio of no.1 to no.2 diesel fuels in the winter blend can vary. Generally, it's about 20 to 80. For the coldest regions, pure grade no.1 diesel fuel may be required.

Even though pure grade no. 1 diesel fuel may seem an excellent solution due to its low gelling point, it's more expensive and has a lower energy content. Running an engine on pure grade no.1 diesel fuel continuously could reduce the fuel system's life.  

Overall, you can use summer diesel fuel before the temperature drops below – 7 °C. Then it's time to switch to the winter blend.

For more information about diesel engine maintenance, please contact us today.

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