For 1990-2009 cars

Caution: Failure to adhere to the following precautions before tire balancing can result in personal injury or damage to components:

• | Clean away any dirt or deposits from the inside of the wheels.

• | Remove any stones from the tread.

• | Wear eye protection.

• | Use coated weights on aluminum wheels.

Important: The tires can be balanced either on-vehicle or off-vehicle, but the off-vehicle balancing procedures are recommended. Off-vehicle methods are better because tire rotation will not affect the balancing. The off-vehicle balancers are also more accurate than the on-vehicle balancers. Off-vehicle balancers can perform dynamic balancing as well as static balancing.

Tire and wheel balancers can drift out of calibration without warning, or can become inaccurate as a result of abuse. The balancer calibration should be inspected every two weeks, and whenever the readings are questionable.

### Tire Balancing Guidelines

Static and dynamic balance are two kinds of tire/wheel balance:

• | Static balance, also called single plane balance, affects the distribution of weights around the wheel circumference.

• | Dynamic balance, or two-plane balance, affects the distribution of weight on each side of the tire/wheel centerline.

Most off-vehicle balancers are capable of checking both types of balance simultaneously.

As a general rule, most vehicles are more sensitive to static imbalance than to dynamic imbalance, with as little as 0.50-0.75 oz capable of inducing a vibration in some vehicles. Vibration induced by static imbalance will cause a vertical or BOUNCING motion of the tire.

Dynamic imbalance results in a side-to-side motion of the tire. This motion is referred to as SHIMMY.

• | Balance all four tires as close to ZERO as possible.

• | Carefully follow the wheel balancer manufacturer's instructions for proper mounting techniques to be used on different types of wheels.

• | Regard aftermarket wheels, especially those incorporating universal lug patterns, as potential sources of runout and mounting problems.

• | Use the correct coated weights on aluminum wheels.

• | Recheck the tire and wheel assemblies for excessive runout after they have been corrected and installed.

• | Evaluate the vehicle at the complaint speed and note if the vibration has been corrected.

• | If the vibration is still present, or is reduced but still unacceptable, you may find one of two possibilities:

- | On-vehicle imbalance

- | Radial or lateral force variation

### Correcting On-Vehicle Imbalance

On-vehicle imbalance may result from components other than the tire and wheel assemblies having imbalance. An on-vehicle high-speed balance or replacement of suspected components may be necessary in order to correct the condition.

Rotors do not have a set tolerance. However, rotors with more than 0.75 ounce imbalance have the potential to cause vibration. The rotors can be inspected for imbalance using either the on-vehicle or the off-vehicle method as follows:

### Checking Rotor Imbalance (On-Vehicle)

1. Support the rear of the vehicle on a suitable hoist. Refer to Lifting and Jacking the Vehicle in General Information.
2. Remove the rear tire and wheel assemblies. Refer to Wheel Removal in Tires and Wheels.

Caution: One or more of the following guidelines may apply when performing specific required tests in the work stall:

• | When a test requires spinning the drive wheels with the vehicle jacked up, adhere to the following precautions:

- | Do not exceed 56 km/h (35 mph) when spinning one drive wheel with the other drive wheel stopped. This limit is necessary because the speedometer indicates only one-half the actual vehicle speed under these conditions. Personal injury may result from excessive wheel spinning.

- | If all of the drive wheels are spinning at the same speed, do not exceed 112 km/h (70 mph). Personal injury may result from excessive wheel spinning.

- | All persons should stay clear of the rotating components and the balance weight areas in order to avoid possible personal injury.

- | When running an engine in the repair stall for an extended period of time, use care not to overheat the engine and the transmission.

• | When a test requires jacking up the vehicle and running with the wheels and brake rotors removed, adhere to the following precautions:

- | Support the suspension at normal ride height.

- | Do not apply the brake with the brake rotors removed.

- | Do not place the transmission in PARK with the drive axles spinning.

- | Turn Off the ignition in order to stop the powertrain components from spinning.

• | When running an engine in the work stall, use the exhaust removal system to prevent breathing dangerous gases.

3. Observe the necessary safety precautions.
4. Run the vehicle at the complaint speed while inspecting for vibration.
5. If the vibration still exists, perform the following steps:

5.1. | Remove the rotors. Refer to Brake Rotor Replacement in Disc Brakes.

5.2. | Run the vehicle back to speed.

6. If the vibration is eliminated, perform the following steps:

6.1. | Remove the rotors one at a time. Refer to Brake Rotor Replacement in Disc Brakes.

6.2. | Perform the vibration test for each rotor.

6.3. | Replace the rotor causing the imbalance.

6.4. | Inspect the balance of the new rotor.

### Checking Rotor Imbalance (Off-Vehicle)

1. Measure the diameter and the width of the rotor.
2. Mount the rotor on a balancer in the same manner as a wheel.

Important: The rotors can only be inspected for static imbalance. Ignore the dynamic imbalance reading.

3. Inspect for static imbalance.

### On-Vehicle Balancing Procedure

The vibration problem may not be correctable with the components removed from the vehicle. An on-vehicle high-speed balancer may be required in order to balance the tire and wheel assemblies while still mounted on the vehicle. On-vehicle balancing will balance the hubs and the rotors simultaneously, and will compensate for any residual runout encountered as a result of mounting the tire and wheel assemblies on the vehicle as opposed to off-vehicle balancing.

Follow the on-vehicle balancer manufacturer operator's manual for specific instructions while keeping the following tips in mind:

### Balancing Tips

• | Do not remove the off-vehicle balancing weights. The purpose of on-vehicle balance is to FINE TUNE the assembly balance already achieved, not to start over again.

• | If the on-vehicle balance calls for more than 1 ounce of additional weight, split the weight between the inboard and outboard flanges of the wheel, so as not to upset the dynamic balance of the assembly that was achieved in the off-vehicle balance.

• | An EVA vibration sensor placed on the fender of the vehicle during the on-vehicle balance is an excellent indicator of the amplitude of the vibration, and the effect that the balance has on the vibration.

• | Evaluate the vibration after the on-vehicle balance in order to determine if the vibration condition has been resolved.

### Lateral Force Variation

Lateral force variation tends to deflect the vehicle sideway, or laterally. Lateral force variation is based on the same concept as radial force variation. A SNAKY belt inside the tire may be the cause of lateral force. The tire substitution method may have to be used before tire replacement.

A lateral force variation condition is rare. The best way to eliminate lateral force variation as a factor in tire and wheel vibration conditions is to ensure that the lateral runout of the tire and wheel assemblies is at an absolute minimum.

The vehicle will WOBBLE or WADDLE at slow speeds of 8-40 km/h (5-25 mph) when lateral force variation is excessive. This condition is usually related to the first-order of tire and wheel rotation.

### Wheel Hub/Axle Flange Runout

Inspect the wheel hub/axle flange when lateral runout occurs during on-vehicle testing but not during off-vehicle testing. Use the tolerances described here only as guidelines. Perform corrections only if the runout cannot be brought to within tolerance.

1. Position the dial indicator on the machined surface of the following components outside of the wheel studs:

• | The hub

• | The axle flange

• | The rotor

2. Rotate the hub in order to find the low spot.
3. Set the dial indicator to zero at the low spot.
4. Rotate the hub again while inspecting the runout.

Specification
Runout tolerance: 0.132 mm (0.0052 in)

### Wheel Stud (Stud Circle) Runout

Use the following procedure whenever the off-vehicle radial runout and the on-vehicle radial runout are significantly different, and the tire and wheel vibration condition has not been corrected.

1. Position the dial indicator in order to contact the wheel mounting studs.
2. Measure the stud runout as close to the flange as possible.
3. Turn the hub to register on each of the studs.
4. Zero the dial indicator on the lowest stud.
5. Inspect the total runout.

Specification
Runout tolerance: 0.25 mm (0.010 in)