Summer Driving Tips
Checking your tires is crucial in the summer. Long road trips with humongous loads and high temperatures can stress your Goodyears to the max. And, obviously, if the tires go, you go! Besides, no one likes to force a mother-in-law into changing a tire on the side of the road. (You want to save her dwindling strength for that big transmission job when you get home!)
2a. Tire Pressure
Make sure that you have the correct tire pressure in all five tires. (In case you never noticed, there's another one in the trunk.) There's plenty of debate about what constitutes “correct” tire pressure, but we suggest going by what your vehicle manufacturer recommends, which should be listed on the side of the driver's door, on the glove compartment door, or in the owner's manual. Don't confuse the “maximum tire pressure” listed on the sidewall of the tire with the “recommended tire pressure” provided by the manufacturer of the vehicle. “Recommended tire pressure” is what you want in your tires. If you're carrying an extra heavy load, follow the recommendation for “heavy loads,“ which is usually listed in your owner's manual.
Ready for some more high-school physics? Remember that tire pressure will increase as the outside air temperature rises. In fact, tire pressure will go up approximately one pound for every 10 degrees Fahrenheit. So, tires that were at 35 PSI back in January when you drove to the slopes could easily be closing in on 45 pounds on a hot July day. Under some conditions that increase in pressure is enough to blow the tire! If nothing else, a tire that's overinflated will wear prematurely and will cause the car to handle and brake poorly. By the way, while you're out there checking the air in those tires, toss that stupid pencil-style pressure gauge in the dumpster where it belongs and get an accurate, dial-type gauge.
You also have to remember friction. As you drive, there's friction between the tires and the road. Friction means heat--and heat means an increase in tire pressure. So, here's what to do about your car's tire pressure: Check the tire pressure before you start driving. If the recommended pressure is 35 PSI, for example, it means 35 PSI before you start driving. If you check the tire pressure when you stop to get gas two hours later, it will be much higher than 35 PSI. If you check it at this point—after you've been driving--there is no way to know what the correct tire pressure should be. You'll be tempted to let air out of the tires, because the tire pressure will be greater than 35 PSI. Do not do this, because the tires will be under inflated.
Most tires now have built-in “wear bars,” which are indicators that appear when your tire is worn and should be replaced.
2b. Tire Treadwear
Of course, you should always check the condition of your tires' treads. The minimum acceptable tread depth is 3/32 inch. This is about the distance from the edge of a penny to the top of Abe's head. But, if we were leaving on a trip, we wouldn't want the minimum tread. Because somewhere in the middle of the trip, you're going to be below the minimum. So do you want to buy tires from the guy down the street, or from Uncle Luke's Gas Station and Charm School in the middle of the Bonneville Salt Flats? Why not takethe trip on brand-new rubber?
While you're looking at the tire tread, keep an eye out for an uneven wear pattern. “Uneven” means the tire is moreworn on one edge. This usually means you need a wheel alignment. Also, run your fingers along the tread and feel for lumps. The presence of lumps could mean that the tire is not balanced correctly. Don't be cheap! This is no time to try to save a few bucks. If you're close to needing tires,get them now.