There are several common misconceptions concerning car maintenance. As Mark Twain once wrote, it’s not the things you don’t know that get you, it’s the things you think you know but don’t”.
Myth: Air conditioning hurts fuel economy
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Although air conditioning puts more of a load on the engine, opening windows to cool down can increase vehicle drag. The difference in efficiency between using air conditioning and a wound-down window varies depending on factors like the speed at which you’re driving and the temperatures inside and outside the vehicle. The difference is so marginal, however, that we recommend just using the air conditioning to keep the driver alert and comfortable.
Myth: Let your engine warm up for a minute before driving
This advice applied more to the cars of yesteryear than to modern cars. Todays’ cars warm up quickly, and you’re likely to lose more on wasted fuel than you gain by ensuring that the engine is fully warmed up before you drive. Rather simply avoid revving high in the first few minutes of driving your car.
Myth: You’ll get more fuel for your money if you fill up in the morning
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Cooler gasoline is denser than warmer gasoline, so the thinking is that your money goes further when it’s cold. However, most gasoline is stored beneath ground, where the temperature changes very little, it at all, over a 24-hour period. The temperature of the gasoline in the pump itself might change, but that on its own isn’t enough to warrant the extra effort involved in ensuring you fill up when it’s still cool.
Myth: Genuine car parts are superior to “after-market” replacements
Car manufacturers are often the source of this myth. The fact is many “non-genuine” car parts are manufactured from superior materials to those used in vehicles’ stock parts. Some cars’ original parts, in fact, are inferior and are improved upon in after-market parts. Even going so far as to call them “pirate-parts” or “counterfeit”, car-manufacturers would much rather you paid a large premium on their brand than pay a fraction of the price for replacement parts that do the job just as well, if not better.
Myth: When brake fluid is low, just top it up
When your brake pads become worn, the level of brake fluid drops a little. This can help you detect wear on the brakes. If the brake fluid level is continually dropping below the low mark on the reservoir, either your brakes are very worn or the brake fluid is leaking. This means it’s important to have the brake system repaired.
Myth: Inflate your tires to the pressure seen on the inside tire’s sidewall
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The pounds per-square-inch value on the inside tire’s sidewall is the maximum tire pressure that the tire can safely hold at different loads, rather than the automaker’s recommended pressure. The recommended pressure, which gives the best balance of breaking, handling, ride comfort and gas mileage, is usually found on the doorjamb sticker, cubby hole or inside the gas-tank lid. Remember, driving with the tires even slightly under- or over-inflated can compromise fuel efficiency, handling and braking, and increase general wear and tear on the tires.
Myth: Premium gas is better for your car
For most vehicles, running on regular grade, or unleaded, fuel is just fine. Using premium gas in these cars won’t hurt, but it won’t improve performance either and will cost a lot more. Typically premium gas is worth the extra money only for running hotter, high-compression engines, such as those in certain high-end luxury vehicles.
Myth: Maintenance should be performed by the dealership
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As long as maintenance is performed on schedule, any auto-repair shop can do the work. If you’re knowledgeable or prepared to put in the hours to learn how the inside of a car works, you can even do the work yourself.