Taking care of your tires is a critical aspect of car maintenance. Good, well-maintained tires improve vehicle handling, protect you from breakdowns and avoidable accidents, and improve fuel economy, according to the National Highway Transportation Safety Administration.
Here’s a basic course in taking care of your tires, so they can in turn keep you safe.
Choosing the Right Tires
When the time comes to buy a new set of shoes for the car, style doesn’t matter much.
Instead of looking for something in just the right color or with the perfect heel, when you buy tires, you are looking for something that will perform like a sleek pair of running shoes and have the strength of a solid pair of hiking boots.
But if style is important—if raised white letters or a racy red stripe are gotta-haves—look for them after you have chosen a tire with the right tread and size for your vehicle.
Just like with shoes, the most important determinant of comfort and safety is size. Buy tires that are the same size as the ones that came on the vehicle when it was new. Unless you have changed the wheel size, your car was designed to wear specific tires.
Check the tire placard, which is located inside the driver’s door, in the glove box or trunk lid, or in your owner’s manual.
The tire size is a combination of letters and numbers, such as P215/65R15. The “P” means it’s for passenger vehicles, the next three digits are width in millimeters from sidewall to sidewall. (The larger the number, the wider the tire.) The number after the slash is the aspect ratio, or the relationship of the height to the width. (A number of 70 or smaller indicates a tire with a short sidewall best suited for sharp handling on dry pavement.) The “R” means radial, which almost all tires are these days. The last two digits are the rim diameter, or how big around your wheels are.
Don’t Let Your Tires Go Bald
Pay attention to the tread. Good tread keeps your tires from slipping on wet roads. It’s easy to spot a bald tire, but it’s much safer to change them before you get to that spot. Consider replacing your tires when there’s just one-sixteenth of an inch of tread left.
One way to check is to look for sections of rubber spaced in the grooves of the tread. When you see what looks like a stripe across the width of the tire, it’s time to change the tire.
Another way to check is with a penny. Hold the penny with Lincoln’s head upside down in the groove. If you can see the top of Lincoln’s head, it’s time for new tires.
It’s usually best to replace all four tires at once. With a new set, you can be sure all your tires are the same quality and condition.
If your budget is tight, replace two tires. Have the mechanic put the new ones where they’re needed most—in front. Take the two best remaining tires and put them on the back.
Keep Tires Inflated
You can stretch the use you get out of a set of tires by practicing good tire maintenance.
The most important thing is keeping your tires properly inflated. Under-inflated tires and overloaded vehicles are the primary causes of tire failure. A blowout at street speed can cause a serious accident.
You can find the correct inflation pressure and maximum load on the placard or in your owner’s manual. The tire pressure number printed on the side of the tire is not the one you should use. That’s the maximum pressure the tire can take. Pressure is measured in pounds per square inch, also known as psi.
Load is the lesser worry. Unless you regularly haul a trunkload of stones or pull a heavy trailer, you are most likely well within the load limits.
Inflation, however, is something you need to check regularly. Buy an inexpensive tire gauge at an auto parts or discount store and keep it in the car.
All tires can lose air over time. It’s impossible to tell if the tire is under-inflated just by looking at it.
Check your tires at least once a month, after the car has been sitting for at least three hours. Check the pressure with your gauge at the valve stem, the little nozzle toward the inside of the tire. Unscrew the cap and put the head of the gauge over the nozzle until you hear a short “pfft” sound. The gauge will show you how much pressure is in the tire.
If there’s too much, let a little air out of the tire with the help of your gauge. There’s usually a small knob on the head. Press it down on the small pin in the center of the nozzle. That releases some air. Recheck the pressure with your gauge.
Under-inflation is more common than over-inflation. If the tire doesn’t have enough pressure, go to the air pump at a nearby service station and add air. Put the head of the pump on your capless nozzle and push until you hear a “pfft.” Many pumps automatically start pumping, while others may have a handle you have to squeeze. Check your pressure again with your gauge until the tire is about 1 psi over the recommended amount. (Remember, warm tires show higher pressure, and you had to drive to the service station.) Check the tires again when they are cold to see if you need to add more air.
Rotate Every 5,000 Miles
Tires need to be rotated to maintain even wear. This is something best left to your service garage or tire store. Usually, tires should be rotated about every 5,000 miles. Check your owner’s manual.
You also need to be sure your tires are properly aligned and balanced. Usually, this is checked when you take the car in for a checkup, but if you feel vibration or shaking, take the car in for an alignment and balance check.
Balancing wheels involves taking them off the car and placing them on a balancing wheel. If they are out of balance, a small lead weight is snapped on the rim to offset the heavy spot. Alignment requires special machinery that can check the angle of the wheels on the vehicle’s frame and adjust it if it’s out of whack.
It usually takes some event to knock a wheel out of balance or alignment. Losing a lead weight will unbalance a wheel, and something as simple as driving hard over a curb or hitting a pothole can affect alignment.
Fixing a Flat
If you get a flat tire, it might be possible to repair it. A hole in the tread from a nail, for example, can be plugged and patched. That involves a mechanic taking the tire off the rim, inserting a plug in the hole and patching it on the inside.
If you get a hole in the sidewall, however, it’s time for a new tire.
In conclusion, tires, like shoes, play an important role in getting us where we need to go. Tires, like shoes, wear out over time. Tires, like shoes, should be replaced in pairs. You wouldn’t wear one new shoe with one that’s been in your closet for a couple of seasons, would you?