When it comes to maintaining your car, common misconceptions abound. And even the best intentions can lead you to spend more money than necessary or even compromise your safety. Here are a few common car care myths that can do more harm than good.

Myth: A dealership must perform regular maintenance to keep your car’s factory warranty valid.

Reality: As long as the maintenance items specified in the vehicle owner’s manual are performed on schedule, the work can be done at any reputable auto-repair shop. If you’re knowledgeable, you can even do much of the work yourself. Always be sure to keep accurate records and receipts to back you up in case of a warranty dispute on a future repair.


Myth: Inflate tires to the pressure shown on the tire’s sidewall.

Reality: The PSI (pounds-per-square-inch) or kPa (Kilopascal) figure on the side of the tire is the maximum pressure that the tire can safely hold, not the automaker’s recommended pressure, which provides the best balance of braking, handling, gas mileage, and ride comfort. That figure is usually found on a doorjamb sticker, in the glove box, or on the fuel-filler door. Perform a monthly pressure check when tires are cold or after the car has been parked for a few hours.

 

Myth: If regular-grade fuel is good, premium must be better.

Reality: Most vehicles run just fine on regular-grade (87 octane) fuel. Using premium in these cars won’t hurt, but it won’t improve performance, either. A higher-octane number simply means that the fuel is less prone to pre-ignition problems, so it’s often specified for hotter running, high-compression engines. So if your car is designed for 87-octane fuel, don’t waste money on premium.

 

Myth: After a jump-start, your car will soon recharge the battery.

Reality: It could take hours of driving to restore a battery’s full charge, especially in the winter. That’s because power accessories, such as heated seats, draw so much electricity that in some cars the alternator has little left over to recharge a run-down battery. A “load test” at a service station can determine whether the battery can still hold a charge. If so, some hours on a battery charger might be needed to revive the battery to its full potential.

 

Myth: Let your engine warm up for several minutes before driving.

Reality: That might have been good advice for yesteryear’s cars but is less so today. Modern engines warm up more quickly when they’re driven. And the sooner they warm up, the sooner they reach maximum efficiency and deliver the best fuel economy and performance. But don’t rev the engine high over the first few miles while it’s warming up.