Suburban 1/2 Ton 4WD V8-5.3L VIN Z Flex Fuel (2006)
Alignment: Service and Repair
Trim Height Inspection
Trim Height Inspection Procedure
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:
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Ensure the vehicle is on a level surface, such as an alignment rack.
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Remove the alignment rack floating pins.
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Set the tire pressures to the pressure shown on the certification label.
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Inspect the fuel level. Add additional weight if necessary to simulate a full tank.
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To ensure proper weight distribution make sure the rear storage compartment is empty.
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Close the doors and hood.
Z Height Measurement
Important: K 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 ground. Cross vehicle Z heights should be within 12 mm (0.47 inch) to be considered
correct.
Place a hand on the front bumper and jounce the front of the vehicle. Ensure 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 lower 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 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 . See:
Suspension/Specifications/Trim Height Specifications
Z Height Adjustment
