How to help your car cope with extreme heat

shiny sun shade
Sun shades are a proven way to keep the temperature down in your car’s interior. Whether they do it stylishly is your call. They can be shiny and boring, for instance.

sun shade with cartoon characters
Sun shades can also be whimsical, as Dewayne Williams of Frederick, Maryland, illustrates.

wonder woman sun shade
Others would argue that the best choice in sun shade style is less whimsical and more comical.

shiny sun shade
sun shade with cartoon characters
wonder woman sun shade

Extreme heat can stress your vehicle’s tires, battery and radiator coolant, but taking a few precautionary measures might help keep you and your car from being stranded along the side of some road.

To prevent tire trouble

The time to check tire pressure is before you start driving.

“Driving in hot weather, you need to always check your tire pressure on all tires, including the spare,” said Mike Quincy from Consumer Reports’ Auto Test Center.

Having lower-than-recommended pressure causes tires to flex more than they should. That’s bad for gas mileage, causes premature wear and allows tires to build up heat much easier, which can lead to tire failure.

Check fluid levels

“Probably the most important fluid to check is the coolant level,” Quincy said, adding that it shouldn’t be more than a few years old. “If you haven’t [changed it] in a while, it probably needs to be done.”

Beware old batteries

Batteries that are 4 of 5 years old are near end of life and more susceptible to stress caused by extreme heat. Check to make sure terminals and cables are securely attached and free of corrosion. “If the battery has removable caps, check its fluid level,” Quincy said. “Top off as needed with distilled water.”

While extreme heat is harder on batteries than extreme cold, Quincy believes you don’t have much to worry about with relatively new cars.

Crack the correct windows to cool off quickly

To push hot air out of a car that’s been parked, crank up the fan when you start driving and open just the rear windows for about 10–20 seconds.

“Opening the front windows is actually just going to keep buffeting the hot air in the back and all around the car,” Quincy said.

Also, don’t waste time and gas letting your car run awhile before you go. “Your car’s air conditioning system actually works a lot better when you’re actually driving,” he said.

Do you own a windshield sun shade?

Sun shades come in many varieties: plain and shiny; artistic (Vincent Van Gogh’s “Starry Night” painting, for example); goofy (e.g., cartoon characters who appear to be driving the car); or curious (such as one making a car appear as though it’s filled with bees).

Don’t be too alarmed by extreme temperatures. Consumer Reports points out that automakers test their vehicles in extremely hot environments, such as Death Valley. Their experts believe you shouldn’t be afraid to hit the road even if it is 100 degrees outside.

Kristi King

Kristi King is a veteran reporter who has been working in the WTOP newsroom since 1990. She covers everything from breaking news to consumer concerns and the latest medical developments.

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