Tire Care

Proper inflation is essential for the performance and longevity of the tire. It’s also essential for the ride quality and safety of your vehicle. Your tires carry the entire weight of your vehicle. They cannot do their job properly when underinflated or overinflated. Operating your tires underinflated can also result in a tire failure.

Check Pressure Once a Month

• It’s possible for a passenger tire initially inflated to 35 psi (pounds per square inch) to lose 1 psi each month.
• Be sure to properly check all four tires cold once a month and before a long trip.
• Whether you have a full-size or mini spare, make sure that it is properly inflated as well.

Check Pressure Once a Month

If you don’t know the proper inflation air pressure for your tires, what do you do?

Easy. Check one of the following places on your vehicle:

• In the vehicle owners manual.
• On the vehicle’s door jamb. (Often, a vehicle information placard is located on the door jamb along with the recommended tire inflation pressure.)
• Inside the fuel hatch filler flap. (in some vehicles).
• The glove compartment door. (in some vehicles).
• But NOT on the tire. The inflation pressure shown on the tire sidewall is only the maximum tire inflation pressure. In most situations, the vehicle manufacturers recommended tire inflation pressure is shown on the vehicle placard. However, on some older vehicles, the recommended pressure listed by your vehicle’s manufacturer may be shown as two numbers: One for city speed driving and normal load and one for highway speeds and/or maximum capacity vehicle load. Be sure to inflate your tires to the recommended inflation pressure for each type of driving situation.

How to Properly Check Tire Pressure

1. Beware of public pressure gauges at gas stations. They are often abused and unreliable.
2. Purchase a good pressure gauge and check it for accuracy at your local BJ’s Tire Center.
3. Check your tires cold – before you’ve driven even one mile or at least three hours after the vehicle has been stopped.

Inflation Tips

1. Air expands when it’s hot and contracts when it’s cold.
2. It’s best to inflate your tires in the morning before the day’s heat.

Valves and Valve Caps

When it comes to proper tire pressure, the tire’s valve is a very important maintenance item. Valves are ordinarily made of rubber, so they can deteriorate over time. Replace them when you buy new tires. At high speeds, a cracked, deteriorated rubber valve stem can bend from centrifugal force and allow air loss.

The valve cap is also an important item. Buy high-quality valve caps that can help contain the tire’s air, should the core of the valve fail for any reason. Valve caps also keep out moisture, which could freeze and in turn depress the valve core, causing air loss. The cap also keeps out dust and dirt particles, which could also interfere with the proper operation of the valve core and cause air loss.

Balancing compensates for the weight of the tire and wheel assembly after the tire is mounted. A wheel is out of balance when one area is heavier or lighter than the rest. This can cause eccentric treadwear and vibration, plus increase the stress on the front-end parts, causing them to wear prematurely.

At the first sign of vibration or irregular treadwear, your vehicle should be thoroughly checked for wheel balance, alignment, and for worn or broken mechanical parts.

Why Balancing Is Important

Balancing means compensating for both the weight of the tire and wheel after the tire is mounted. A wheel is out of balance when one area is heavier or lighter than the rest. This:

• Can cause off-center treadwear
• Can cause vibration
• Can increase stress on front-end parts
• May cause front-end parts to wear prematurely

When to Balance

Have your wheels balanced when:

• A tire is replaced
• A balance weight is moved or removed
• You purchase new tires

How a Wheel Is Balanced

To balance the wheel, your mechanic will use a balancing machine to determine where the heavy spots are. Weights are then attached to the exterior or interior of the wheel to counteract centrifugal forces acting on the heavy areas when the wheel is turning. This will eliminate vertical bouncing (static balance) and side-to-side wobble (dynamic balance).

Regular rotation helps extend the life of your tires, saving time and money in the long run.

For rotation, each tire and wheel is removed from your vehicle and moved to a different position. This ensures that all of the tires wear evenly and last longer. If no period is specified in your vehicle owners manual, tires should be rotated every 6,000 to 8,000 miles. If you have a full-size spare, it should be included in the rotation process.

Alignment generally refers to the adjustment of a vehicle's front and rear suspension parts. Proper alignment helps ensure that your vehicle handles correctly and will help increase the life and performance of your tires.

Why Alignment Is Important

Proper alignment helps ensure that your vehicle handles correctly and will help increase the life and performance of your tires.

When to Check Alignment

Daily impacts such as potholes and railroad crossings, as well as more severe circumstances, e.g. accidents, can knock your vehicle out of alignment. You should have the alignment checked if:

• You’ve hit something
• You see a wear pattern developing on the shoulders of the tires
• You notice a difference in your vehicle’s handling

How Wheels Are Aligned

Alignment involves adjusting the angles of the wheels so that they have the proper toe in and camber. The three main adjustments made in alignment are camber, caster, and toe. View the animation below to understand the three main adjustments made during alignment, or continue reading for more details.

Camber

Camber is the angle of the wheel when viewed from the front of the vehicle. If the wheel leans too far, uneven wear will occur.

• Positive camber is when the top of the wheel is leaning away from the car. Too much positive camber wears tires on the outside.
• Negative camber is when the top of the wheel is leaning in toward the car. Too much negative camber will wear tires on the inside.

The camber angle is designed and adjusted for each vehicle to keep the tires flat on the ground during a turn. If there is too much difference between the camber settings on the front wheels, the vehicle will tend to pull sharply to one side.

Caster

Picture a caster wheel found on furniture or a shopping cart. When you push a shopping cart equipped with caster wheels, it tends to roll in a straight line because the wheels line up.

On a vehicle, caster is the forward or rearward tilt of the steering axis, measured from the top of the tire, as viewed from the side. The axis is formed by extending an imaginary line through the upper and lower steering knuckles. The line extends through the upper and lower ball joints on vehicles with front control arms, and through the lower ball joint to the center of the strut mount on cars with struts.

• Positive caster occurs when the angle is toward the rear of the vehicle. Positive caster has the effect of making your front wheels act as if your car was being pulled from the front so that they will line up behind the point of pull, like a child’s pull toy.
• Negative camber occurs when the angle is to the front of the vehicle.

Caster is set so that your vehicle will tend to go straight ahead. Caster affects your vehicle’s low-speed steering and high-speed stability as well as how well your vehicle drives in a straight line (on-center feel). Negative caster will cause your car to "wander" and make it feel unstable at high speeds. Positive caster causes hard steering and can also result in excessive road shock and shimmy. Caster does not affect tire wear

Toe

Toe is the difference in the distance between the front of the tires and the back of the tires. Toe settings affect the handling characteristics of a vehicle while turning.

• Toe-in is when the front ends of the tires are closer. Toe-in introduces understeer going into a curve. If the tires are toed-in too much, the tread will be "worn" off, starting from the outside edges.
• Toe-out is when the rear ends of the tires are closer. Toe-out can introduce oversteer in a curve and makes the vehicle feel like it is "diving" into the turn sharply. If tires are toed-out, the wear will start from the inside. This type of wear is called "feathering" and can be felt by running your hands across the tread of the tire.