Tires can have an effect on gas mileage especially in the long term. Driving with tires that are under-inflated, worn, too tall or overly wide for the car's manufacturer's recommendation will decrease your gas mileage, undoubtedly. Keeping the proper tire inflated to the proper pressure will always give you the best opportunity for fuel economy when it comes to those four wheels keeping you on the road. Don't ignore this area of your vehicle when it comes to maintaining respectable gas mileage and safety.
- Under-inflated tires create drag and pull on the vehicle, which will create more friction between the road and the tire as a result requiring additional power from the engine to keep the vehicle moving at the desired speed. Check for the proper tire pressures near the driver's door latch area or on the B-pillar. There should be a sticker, installed by the car manufacturer, to tell you what your front and rear tire pressures should be. Check and adjust them regularly.
- Tires that are worn probably aren't as big a factor in the gas mileage area as low tire pressures are, but you shouldn't overlook the fact that you may lose traction from time to time, which could cause a small amount of lost fuel mileage. This is more of a safety issue than a gas mileage problem. Losing traction in a rainstorm may possibly cause you to hydroplane and lose control of the vehicle. Don't take your chances on worn tires, gas mileage or otherwise.
- Tires that are too tall for your particular vehicle will only rob energy from it. Taller tires will take more energy to get moving to the desired speed and if you do a lot of starting and stopping this is going to be noticeable in the gas mileage department. Tires that are too small won't help either, stick to the manufacturer's recommendation when it comes to tires, you can't go wrong.
- Tires that are wider than the original will also affect gas mileage. A wider tire is going to have more surface area contacting the road and that just means more friction to overcome. Thinner tires would actually increase your mileage, but that's another safety issue. Your tires need to match the maximum payload on your vehicle to keep you on the road and also to keep from having a blowout.
- When it comes to bias-ply or radial tires, well there usually isn't much of a choice anymore. Bias-ply tires are pretty much a thing of the past for the average family car or truck. Radial tires have taken the high road for convenience, safety and gas mileage.
- When talking about tread designs, anything that is aggressive, like off-road tires, will drop the gas mileage. You have to decide what you're planning on using the vehicle for when it comes to tread design. Weigh the factors when it comes to gas mileage or better traction in bad weather or off-road conditions. That's a choice you'll have to make.
The effect tires have on gas mileage may not be substantial at first but in the long run having the correct tire that is properly inflated will still help you save at the gas pump.