Sierra Denali Classic AWD V8-6.0L (2007)
Alignment: Testing and Inspection
Trim Height Inspection
Trim Height Measurements
Trim height is a predetermined measurement relating to vehicle ride height. Incorrect trim heights can cause bottoming out over bumps, damage to the
suspension components and symptoms similar to wheel alignment problems. Check the trim heights when diagnosing suspension concerns and before
checking the wheel alignment.
Perform the following before measuring the trim heights:
1. Make sure the vehicle is on a level surface, such as a alignment rack.
2. Remove the alignment rack floating pins.
3. Set the tire pressures to the pressure shown on the certification label. Refer to Vehicle Certification, Tire Placard, Anti-Theft, and Service Parts ID
Label.
4. Check the fuel level. Add additional weight if necessary to simulate a full tank.
5. Make sure the rear compartment is empty except for the spare tire.
6. Close the doors and hood.
Z Height Measurement
Important:
Torsion bar models only, the Z height must be adjusted before the alignment.
The Z height dimension measurement determines the proper ride height for the front end of the vehicle. Vehicles equipped with torsion bars use a
adjusting arm in order to adjust the Z height dimension. Vehicles without torsion bars have no adjustment and could require replacement of suspension
components.
1. Important:
All dimensions are measured vertical to the ground. Cross vehicle Z heights should be within 12 mm (0.47 inch) to be considered correct.
Place hand on the front bumper and jounce the front of the vehicle. Make sure that there is at least 38 mm (1.5 inch) of movement while jouncing.
2. Allow the vehicle to settle into position.
3. Measure from the pivot bolt center line (2) down to the lower corner (5) of the steering knuckle (1) in order to obtain the Z height measurement
(4).
4. Repeat the jouncing operation 2 more times for a total of 3 times.
5. Use the highest and the lowest measurements to calculate the average height.
6. The true Z height dimension number is the average of the highest and the lowest measurements. Refer to Trim Height Specifications.
Z Height Adjustment