The tires are the only part of the car that touch the road. They are crucial to a vehicle's performance, safety and even fuel economy.
"Tires affect braking, turning, traction," says Tom Hix, manager of Firestone Complete Auto Care in St. Charles.
They're not cheap, either. A new tire can range from $75 to $200 for pickups and SUVs; a whole set for some performance cars and luxury models can climb to near $2,000.
But potential cost shouldn't deter you. Understanding your tires and addressing these four common issues will help your vehicle perform as intended.
Worn treads: The days of eyeballing the tire or kicking the sidewalls are over, Hix says. "You have to look at the inside edge."
If the tread is bare or breaking apart, it should be time for a change.
If you can't tell, fish out a penny to test the depth of your tire treads.
Put it in the tire treads with Lincoln's head pointing down to the center of the tire. If his head is covered, there is enough tread left; if the tread can't even give Lincoln a haircut, it's time for a new set.
Old tires: Tires on vehicles that sit for 6 months out of the year can be due for a new set, even if the treads are good. "As the tire gets older, the rubber gets harder, so you start losing wet weather traction," Hix warns. He recommends getting new tires if they're five to six years old, especially in areas with seasonal weather changes.
Misalignment: To prevent uneven wear, tires should be rotated every 5,000 to 7,000 miles, according to Hix. Uneven wear can lead to the steering pulling to the left or right. This will increase road noise inside the vehicle that, over time, may be hard to notice until the car is fitted with a new set of tires, like a new pair of shoes.
The tire rotation may be different for FWD or AWD cars, so it's not as simple as swapping the front side for back side. Hix was sure to remind us that Bridgestone/Firestone offers free tire rotations.
Proper inflation: Like filling the tank, every car owner knows how to fill the tires with air. Yet many people get it wrong and shorten the life of their tires.
"The biggest problem I see is improper air pressure," Hix says.
The air pressure listed on the side of the tire is the max pressure the tire will hold, not the optimal tire pressure for the car to run on. Check the sticker on the inside door sill or consult the owner's manual.
"Underinflated tires will generate more heat, which increases wear," Hix explains. "Overinflating them decreases the contact patch, or amount of tread touching the road, which will affect stopping, cornering — everything."
If your vehicle needs new tires, you could be in for a confusing process. There's a tire for every season, it seems, and the choice between dozens of foreign-sounding tire models can be daunting.
Consumer Reports just vetted 150 tire models through a battery of tests that took more than one year to complete, and broke down the recommendations into six categories: Michelin Defender is the top all-season tire, Continental PureContact is the top performance all-season tire, Pirelli P Zero is the top ultra high performance summer tire, Michelin LTX M/S2 is the top all-season truck tire, Hankook Dynapro AT-M is the top all-terrain truck tire, Michelin X-ice XI3 is the top winter tire.
All-season tires are a jack-of-all-trades, master-of-none trade-off. They're good for the majority of drivers who don't plan on using a lift to swap out seasonal tires at home, or who won't store a set at the mechanic's shop because, as with the doctor's office, they stay away until necessary.