What Happens to Your Fuel When Temperature Drops?

The Impact of Proper Winter Trailer Maintenance 

Dropping temperatures are a constant concern for any driver. During the coldest months, diesel fuel can freeze, putting trucks at risk for a wide range of concerns. Understanding the impact of very cold temperatures on fuel is important for all drivers, as is performing proper trailer maintenance to keep your commercial vehicle running efficiently.

How Temperature Changes Affect Your Truck Fuel

Even though oil companies do their best to change over to winter diesel as winter approaches, several things can happen to diesel fuel when temperatures fall, including:

• Gelling can occur: Though somewhat rare, diesel fuel can become gel-like. That’s due to the paraffin wax that’s in the fuel. For this to happen, the fuel has to stay cold for a long period of time. That’s why it’s less likely to happen in day-to-day operations but more common if a vehicle has been sitting for some time in extreme cold conditions.
• You may see clouding: As paraffin begins to reach a solid point, it creates a cloudy appearance in the fuel. It’s not quite gel-like at this stage, but it’s still thick enough to cause consistent problems. It can get into the filters and clog them or may impact engine performance overall, dropping fuel efficiency while it does so. It’s critical to schedule engine maintenance if you suspect this is occurring. 
• The fuel may reach its pour point: Cold temperatures can also lead to so much thickening of the fuel that it cannot flow. The pour point refers to the point in which the fuel no longer flows easily. Various factors can cause this to occur, such as the refining process of the fuel or any additives placed in it.

Don’t Overlook the Most Common Problem with Truck Fuel

While the above are all problems that can occur, they are not as common as the presence of water in your fuel. When water gets into any point of the fuel system and temperatures drop, that creates clogs in fuel lines. It can make it impossible for fluid to move through the fuel filter properly, starving the engine of the fuel it needs. 

To determine if water is the culprit, you will likely need to drain the fuel line and check the fuel filters. If you notice ice chunks (even very small ones) present, that’s due to freezing water in the fuel lines. If you notice the fuel is thick and more gel-like, rather than having specks of frozen water, you know it’s the fuel itself causing the problem. During regular winter maintenance appointments, your trusted truck mechanics will normally check for this issue.

How Winter Blend Diesel Affects Fuel Economy 

Another important aspect to keep in mind is how cold temperatures can impact your fuel economy. Most of the time, fueling stations move to a winter blend of fuels to minimize the impact on engines. However, the additives that are mixed in to achieve this change the cetane level of the fuel. The direct result is a loss of up to three-quarters of an MPG in a truck’s fuel efficiency.

Cold Temperatures Impact Trailers Too!

Other actions, including on and off-the-road trailer maintenance in winter, should be performed religiously to maximize fuel economy, road safety and uptime. For example, issues with frozen brake hoses or snow and ice on the trailer roof, while not directly related to the fuel itself, can definitely affect fuel economy.   

Here are some common items for a driver to check during winter trailer maintenance:

1. Frozen or semi-frozen brake hoses.
2. Check if brakes are dragging.
3. Snow can alter the aerodynamic form of the trailer and accumulated snow flying off is very dangerous to other drivers.
4. Underinflated tires (due to temperature drop) eat up more fuel and make winter handling more precarious.
5. Damaged or disconnected wiring to brake lights and turn signals, frozen wire damage.
6. Snow or ice packed into trailer crossmembers or frame.

Schedule Timely Tractor & Trailer Maintenance Appointments 

If you suspect a problem with your truck’s fuel for any reason, it’s best to contact a truck service station immediately. Don’t continue to drive with thickened fuel, as it can damage your engine. Similarly with trailers, if there is a problem you can’t fix on the road, bring it in.

STTC offers 24/7 emergency road service to help you get back on your route. If you notice changes to your fuel, or you want to schedule routine truck and trailer maintenance, give us a call now at 610-954-8473 or contact us online.