The Freezing Point of Gasoline and Its Effect on Your Car

There are plenty of things to worry about when it comes to winterizing your home and car so that the dramatically dropping temperatures don’t have any unwanted side effects.

“Modern vehicles are pretty resistant to cold weather, but it does impact things,” says John Vorisek, founder at Repair Surge. “The most common would be the battery, because batteries are less efficient at lower temperatures. It can also affect the fluids and tire pressure.”

But while it’s a good idea to be prepared for the changing of the seasons, that does not mean that all of the concerns around winterizing your vehicle are worth worrying about. You may have heard before that if you keep less than half a tank of gas in your car during the winter the gasoline could freeze in place and ruin your gas tank. This might seem like a real concern at first, but it falls apart under any further investigation.

Here’s more about that, plus other tips for maintaining your car in cold weather.

Does Gasoline Freeze?

In order for gasoline to freeze, it needs to be held at temperatures of around -100 degrees F. That number will vary depending on the components that make up your gasoline (octane, for example, has a higher freezing point), but the point remains the same. The freezing point of gasoline is so extreme that it’s highly unlikely that temperatures in your area would ever drop to the point where gasoline is freezing in your vehicle, and it’s even more unlikely that anyone would be driving or want to drive in those conditions.

But that does not mean that cold temperatures won’t have any negative effects on your gas tank. “Gasoline freezing is really unlikely unless you live in the Arctic, but the part about keeping more than half of your tank full is still a good idea because it prevents condensation in the tank, which can lead to water contamination,” says Tomer Ruderman, owner at Car Keys Ottawa. “That water can freeze, block fuel lines and cause problems starting your car.”

The cold can also cause gasoline to break down and separate into its components, turning into a useless gel. Diesel fuel has a lower freezing point than regular gasoline, which is why fuel companies typically provide a summer and winter diesel blend.

Winter driving brings with it a lot of legitimate potential problems that it pays to be prepared for. Unless you live way up north, though, you don’t really have to worry about your gasoline freezing over.

Negative Impact of Cold Temps on Your Car

The cold can create a lot of hassles with vehicles, including:

• Thickening engine oil, transmission fluid and other lubricants. “This reduces lubrication and causes startup problems, or worse powertrain damage,” says Tim Rodifer, technical director for Mr. Transmission.
• Weakening the battery, which also makes it harder to start;
• Freezing fluids, like windshield washer fluid that isn’t rated for low temperatures;
• Lowering tire pressure (because cold air contracts), which affects fuel economy and makes the car harder to control (plus tires don’t grip the road as well on ice); and
• In extreme cases, freezing fuel lines.

“For the fluids, winter versions are available that are formulated differently, but it’s usually not a major issue,” says Vorisek. “For the tire pressure, it’s a good idea to check the tires when it gets cold and add some air if needed.”

FAQ

Is anything in your car in danger of freezing when temps drop?

Yes. A few things that can freeze in your car include:

• Door locks that have condensation in them;
• Windshield wiper fluid. “But you can find winter windshield wiper fluid, which can withstand lower temperatures and also help break down the ice on your windshield,” says Ruderman.
• Condensation in the gas tank, which can freeze fuel lines;
• Any drinks or medications left in the car; and
• Battery-powered devices can be damaged by severe cold.

“If any part of a vehicle freezes in winter, it’s most likely due to the presence of water,” says Vorisek. “Door locks can freeze for example, but it’s really water in and around the locks that freezes. The same goes for fluids; they’re usually not going to freeze unless there’s unwanted water in the mix. But winter formulations can be used to be safe.”

Can adding fuel additives help your car run better in the winter?

Yes, as long as they’re in line with your vehicle manufacturer’s recommendations.

“Fuel additives can help your vehicle all year long, but be sure to use high-quality products with a good track record and avoid ones that risk voiding your new car warranty,” says Frank Scandura, owner of Frank’s European Service. “Just because the commercial said it’ll help does not mean it will.”

Some of the benefits of additives can include:

• Improved fuel combustion;
• Fuel stability;
• Getting rid of water in the fuel lines;
• Cold start help; and
• Fuel system lubrication.

“When it’s cold outside, the friction in the fuel system can get worse, so some fuel additives have cleaning agents in them that make the engine run more smoothly and efficiently by lowering friction,” says Xavier Sabastian, an author and auto expert with Way.com.

Rodifer also recommends using high-quality winter-grade gasoline to improve performance during cold weather.

About the Experts

• Tomer Ruderman is founder and owner at Car Keys Ottawa, where he works with various vehicles, auto repair shops, garages and organizations on projects large and small.
• John Vorisek is founder at Repair Surge, which he started in 2003 to provide factory-authorized automotive service data to help owners and independent auto repair facilities diagnose vehicles.
• Tim Rodifer is the technical director for the Moran Family of automotive franchisors, including Mr. Transmission/Milex Complete Auto Care where he worked for more than two decades.
• Frank Scandura is owner of Frank’s European Service in Las Vegas, Nevada, has 45 years of automotive experience and has written dozens of articles for AutoTechIQ, a resource for car owners who want to educate themselves about car issues and find trusted repair shops nearby.
• Xavier Sabastian is an author and auto expert with the Way.com auto app.