Rear Suspension

1. Check for leaks on shock absorbers.
2. Check shock absorber operation for stiff, rough or spongy operation.
3. Check condition of rear suspension bushings and rear suspension springs.
If the above checks reveal evidence of excessive wear, deterioration, or improper operation, replace damaged components.

Vehicle Lean
Side-to-side vehicle lean should be verified by measuring the fender lip-to-ground dimension before beginning diagnosis and repair actions. Normal acceptable limits are:
- Maximum of 16 mm (5/8 inch) variance between left and right front wheel lips to ground.
- Maximum of 19 mm (3/4 inch) variance between left and right rear wheel lips to ground.

NOTE: Codes identifying the front and rear spring options and springs are printed on the Safety Standard Certification Label. Replace springs in pairs if one is found to be damaged or worn. If a spring should require replacement because it is damaged, worn or due to a leaning condition, replace only with the same part specified on the label.

In rare instances, the spring codes will not reflect the springs as installed due to a District Special Order (DSO) option or assembly plant substitution. If a DSO option number is shown on the certification label, the District Office can establish whether springs are affected. If the factory-installed springs do not agree with the code printed on the Safety Standard Certification Label (right and left coil or leaf spring part numbers should match [Note the 4x4 front torsion bars have different base part numbers on the left and right sides.]), replace the damaged or worn springs with new springs of the same part number as the damaged or worn springs.
1. Place the vehicle on a flat, smooth surface.
2. Inspect the vehicle for any heavy add-ons that may cause excessive weight on any corner of the vehicle.
- In cases where the excess weight is a snow plow, a rear tailgate lift, etc., the vehicle must be diagnosed with the equipment in place.
- Measure corner weights if necessary.
- Vehicle fuel tanks should be full and the vehicle empty of cargo such as tools, equipment or debris in the pickup box or rear body section.
- Vehicle must be sitting on the wheels and tires and not a hoist, jack or jack stands.
3. Check all wheels and tires:
- Wheels must be same size and design, right and left side on each axle.
- Wheel size and design, tire size and tire design should be as indicated on the Vehicle Certification Label.
- Check the pressure and inflate.
4. Check front and rear suspension. Make sure the same spring is on the left/right front and left/right rear. The front and rear springs have ID tags indicating the part number.
5. Jounce the vehicle's front and rear suspension to normalize the vehicle static ride height.





6. Measure the height of the right and left fender lip openings for both front and rear.
7. Calculate the side-to-side differences for each dimension. If these differences are greater than 16 mm (5/8 inch) between left and right front or 19 mm (3/4 inch) between left and right rear, adjustment/repairs are necessary.

Side-to-Side Lean
1. Verify the customer concern by operating the vehicle.
2. Visually inspect for obvious signs of mechanical and electrical damage; refer to the following chart.





Visual Inspection Chart

3. For driveline noise, refer to Transmission and Drivetrain.
4. If the fault is not visually evident, determine the symptom and proceed to the symptom chart. Symptom Related Diagnostic Procedures