Sierra 1500 4WD V8-6.0L (2007)
Alignment: Service and Repair
Trim Height Inspection
Trim Height Inspection
Trim Height Measurements
Trim height is a predetermined measurement relating to vehicle ride height. Incorrect trim heights can the vehicle to cause bottom 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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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.
*
Check the fuel level. Add additional weight if necessary to simulate a full tank of gas. (One U.S. gallon of gasoline weights approximate 6.5 lbs.
One liter of gasoline weights 0.70 kg)
*
Make sure the passenger and rear compartments are empty, except for the spare tire.
*
Make sure the vehicle is on a level surface, such as an alignment rack.
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For vehicles equipped with automatic level control, make sure that the system is functioning properly.
*
Make sure that all doors, lift gate/trunk and the hood are securely closed.
*
Check for installed after market accessories or modifications that could affect trim height measurements:
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Larger or smaller than production wheels and tires
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Lifting or lowering kits
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Wheel opening flares
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Ground affects
*
Remove the alignment rack floating pins.
Measuring the Z Height
Important: For vehicles equipped with torsion bars, the Z height must be verified 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.
Important: All dimensions are measured vertical to ground. Cross vehicle Z heights should be within 12 mm (0.47 in) to be considered
correct.
1. Lift the front bumper of the vehicle up about 38 mm (1.5 in).
2. Gently remove your hands and let the vehicle settle.
3. Repeat this operation 2 more times for a total of 3 times.
