How good of an idea is it to warm up your car in the cold before driving it? Actually, the results are a mixed bag. Let’s dig in to see what some say and see where the truth really lies.

Image 1: A car driving through snow and ice

Sources such as Consumer Reports and this Honda dealer say it’s a good idea that can increase engine performance and longevity. Others such as Southern Living and this Toyota dealer suggest it can cause more wear and tear on your engine. So, what is it? Is it good or bad? Let’s break it down from an engineering perspective and see what you should and shouldn’t do.

One thing science tells us is that the warmer the liquid, the easier it is to move. That’s because the molecules inside the liquid have more energy when it’s warm rather than when it’s cold. This is also true for liquids like engine oil and transmission fluid, both of which are needed to lubricate the car’s engine and transmission.

Image 2: Engine oil lubricating engine parts

Another thing to keep in mind is that cars idle at higher revolutions per minute (RPMs) right after they start compared to after a few minutes of operation. Science and engineering again tell us that the more work a machine does—including a car’s engine and transmission—the more wear and tear it’ll experience. From this alone, it seems that it isn’t a bad idea to let your car warm up at idle for a little while.

One more thing that warming up the engine can do is warm up other components of your car, such as the differential and driveshafts, and eventually the brakes once the vehicle is driven. This’ll help the car drive better since the brakes are warmer and the differential fluid is warm. Just like the engine and transmission, it’s important to operate these at optimal temperature to help extend your car’s lifespan.

Well, are both Southern Living and the Toyota dealer wrong? Not necessarily. Excessive engine warmup can put more pollutants in the air than necessary. Going back to excessive engine wear, applying the throttle when the car’s warming up can put extra stress on the parts, which can decrease your vehicle’s lifespan. Also, warming up your car longer than needed can waste gas, which you’ll feel at the gas pump.

Image 6: Car exhaust releasing exhaust fumes

Bottom line: it seems like it’s a good idea to warm up your car in the winter, but only for as long as you need to. When the oil temperature on your dash says it’s within range, that’s usually good enough to start driving.

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Warming Up to Face the Cold

Sticking to the Ground

Staying Warm on the Inside