Repair Instructions
Tire and Wheel Balancing
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: Use a known good, recently calibrated off-car two plane dynamic balancer. Use the finest balance mode available in order to perform a perfect balance of the assembly. The center pilot hole is the primary locator. Back cone mounting is recommended. If any assembly calls for more than 7 grams (1/4 ounce) on either rim flange, remove all balance weights and re-balance.
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 according to the manufacturer's requirements.
Tire Balancer Calibration Test
Important: Calibrate the tire balancer according to the manufacturer's recommendations, or use the following procedure.
1. Spin the balancer without a wheel or any of the adapters on the shaft.
2. Inspect the balancer readings.
0-7 g (0.00-0.25 oz)
3. Balance a tire and wheel assembly that is within radial and lateral tolerances to ZERO.
4. Add an 85 g (3 oz) test weight to the wheel at any location.
5. Spin the tire and wheel assembly again. Observe the readings.
* In the static and dynamic modes, the balancer should call for 85 g (3 oz) of weight, 180 degrees opposite the test weight.
* In the dynamic mode only, the weight should be called for on the flange of the wheel opposite the last weight.
6. With the assembly unbalanced to 85 g (3 oz), cycle the balancer five times.
7. Take the balancer readings.
Variation: 7 g (0.25 oz) or less
8. Index the tire and wheel assembly at four separate locations on the balancer shaft, 90 degrees apart.
9. Cycle the balancer with the assembly at each location.
10. Take the balancer readings.
Variation: 7 g (0.25 oz) or less
Tire Balancing Guidelines
Static and dynamic balance are the 2 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 can check both types of balance simultaneously.
As a general rule, most vehicles are more sensitive to static imbalance than to dynamic imbalance. As little as 14-21 g (0.50-0.75 oz) may induce 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, or shimmy.
* Balance all four tires as close to ZERO as possible.
* Carefully follow the wheel balancer manufacturer's instructions for proper mounting techniques for different types of wheels.
* Aftermarket wheels, especially those incorporating universal lug patterns, are potential sources of runout and mounting problems.
* Use the correct coated weights on aluminum wheels.
* Retest the tire and wheel assemblies for excessive runout after correction and installation.
* Evaluate the vehicle at the concern speed and note if the vibration has been corrected.
* If the vibration is still present, or is reduced but still unacceptable, consider these possibilities:
- On-vehicle imbalance
- Radial or lateral force variation
Wheel Weight Usage
Two methods for balancing wheels are the dynamic balancing method and the static balancing method. When using the dynamic balancing method, place the clip-on balance weights on the inboard rim flange (2) and the outboard rim flange (1) at the positions specified by the tire balancer. When using the static balancing method, place the weight on the inboard (2) flange if the weight is 28 grams (1 ounce) or less. If more than 28 grams (1 ounce) is required to balance the wheel, split the total weight required between the inboard rim flange (2) and the outboard rim flange (1).
1 - Type MC (aluminum wheels)
2 - Type AW (aluminum wheels)
3 - Type P (steel wheels)
Important: Special polyester-coated clip-on balance weights must be used on factory aluminum wheels. Polyester-coated wheel weights reduce the potential for corrosion and damage to aluminum wheels.
The two types of approved wheel weights are type MC (1) and type AW (2). Type P (3) wheel weights are for use on steel wheels and can not be used on aluminum wheels.
The contour of the rim flange will determine which type of wheel weight should be used. The clip should firmly grip the rim flange. The weight should follow the contour of the rim flange. Use a plastic-tipped hammer when installing polyester-coated wheel weights in order to avoid damaging the polyester coating.
1 - Adhesive Weight (static balance)
2 - Adhesive Weight (dynamic balance)
Adhesive wheel weights (1, 2) may also be used on aluminum wheels. Use the following procedure in order to install adhesive wheel weights.
1. Determine where the wheel weight is to be placed on the wheel.
2. Ensure that there is sufficient clearance between the wheel weights and the brake components.
3. Using a clean cloth or paper towel, wipe the area with a general purpose cleaner. Wipe the area again with a mixture of half isopropyl alcohol and half water in order to remove any remaining residue.
4. Dry the area with hot air until the wheel surface is warm to the touch.
5. Warm the adhesive backing on the wheel weight to room temperature.
6. Remove the protective covering in order to expose the adhesive tape on the wheel weight. Do not touch the adhesive tape.
7. Apply the wheel weight to the wheel. Press into place with hand pressure.
8. Secure the wheel weight to the wheel with a 90 Newton (20 lb) force applied with a roller.