Operation CHARM: Car repair manuals for everyone.
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Design Height Setting

1. Place the vehicle on a level, flat surface, such as an alignment rack, that will allow access to the underside of the vehicle.
2. Check that all tires are at the preferred inflation pressure and adjust as necessary if they are not.

NOTE: When loosening the lower control arm mounting bolts be sure the alignment adjustment cams do not turn. The cams must stay in their original position so the alignment of the vehicle is not affected.

3. Loosen the mounting bolts for the following suspension components. The mounting bolts must be loosened enough to allow the suspension of the vehicle to move without loading (twisting) the rubber insert of the isolator bushings.
- Front and rear lower control arm to frame bracket mounting bolts.
- Front and rear upper control arm to frame bracket mounting bolts.
- Front upper control arm to pivot bar mounting bolts.
- Front and rear shock absorber to frame bracket mounting bolts.
- Front and rear shock absorber to lower control arm mounting bolts.

NOTE: When the height checking fixtures are installed on the wheels, they must be positioned at the very bottom of the wheel rim. This is required to ensure the height checking fixtures are parallel to the bottom surface of the frame rails, which is required to achieve an accurate vehicle design height measurement.

Vehicle Front Height Checking Fixture Installed:





4. Position the Front Height Checking Fixture, Special Tool 6914, on the inner rim flanges of the front wheels.

Vehicle Rear Height Checking Fixture Installed:





5. Position the Rear Height Checking Fixture, Special Tool 6914, on the inner rim flanges of the rear wheels.

Height Checking Fixture Installation On Wheel:





6. Ensure that the Vehicle Height Checking Fixtures, Special Tool 6914, are correctly attached to the inner rim flange of the front and rear wheels.

NOTE: Note: When lowering the vehicle to its specified design height do not add all the ballast (weight) to the trunk and passenger compartment of vehicle at one time. Add the ballast to the vehicle slowly until the correct distance between the Vehicle Height Checking Fixtures Special Tool 6914, and the frame of the vehicle is achieved.

NOTE: The approximate total weight needed to lower the vehicle to its design height is 400 pounds. The weight distribution in the vehicle i~ approximately 330 in the passenger compartment (165 pounds per seat) and 70 pounds in the trunk. If the spare tire is not in the trunk, approximately 4(1 additional pounds will need to be placed in the trunk to compensate for the tire.

Correctly Ballasted Passenger Compartment:





7. Add ballast weight as required to the passenger compartment of the vehicle to lower the front of the vehicle to the specified design height. Do not over ballast the vehicle. If vehicle is over ballasted, the design height will be incorrect and the special tool can be bent.

Correctly Ballasted Trunk:





8. Add ballast weight as required to the trunk of the vehicle to lower the rear of the vehicle to the specified design height. Do not over ballast the vehicle. If vehicle is over ballasted, the design height will be incorrect and the special tool can be bent.

Measuring Vehicle Front Curb Height:




Measuring Vehicle Rear Curb Height:





9. Check the vehicle's front design height by measuring between the Height Checking Fixture, Special Tool 6914 and the frame rail crossmember. Check the vehicle's rear design height by measuring between the Height Checking Fixture, Special Tool 6914 and both rear frame rails.
10. After ballasting the rear of the vehicle, recheck the front design height to see if the front of the vehicle lifted when rear was ballasted. If necessary, add weight to the passenger compartment of the vehicle, lowering the front of the vehicle back down to the required design height. Keep checking front and rear of vehicle until no further adjustment is required and the vehicle is at the correct front and rear design height.
11. Tighten the mounting bolts for the following suspension components to the specified torques.
- Front and rear lower control arm to frame bracket cam adjustment bolts and nuts to 101 Nm (75 ft. lbs.).
- Rear upper control arm to frame bracket pivot bolts 95 Nm (70 ft. lbs.).
- Front upper control arm to pivot bar mounting end nuts 136 Nm (100 ft. lbs.).
- Front and rear shock absorber to frame bracket mounting bolts 136 Nm (100 ft. lbs.).
- Front shock absorber to lower control arm mounting bolts 136 Nm (100 ft. lbs.).
- Rear shock absorber to lower control arm mounting bolts 190 Nm (140 ft. lbs.).
12. Remove the ballast from the trunk and passenger compartment of the vehicle.
13. Lightly jounce the front and rear suspension of the vehicle to ensure vehicle is settled at curb height. When jouncing the vehicle, the vehicle must be released at the bottom of the jounce cycle. This will ensure the vehicle's suspension will raise the vehicle to the correct curb height at the top of the jounce cycle.
14. Check the vehicle's front curb height by measuring the distance from the center of the front frame rail crossmember to top surface of Vehicle Height Checking Fixture, (at front edge).
15. Check the vehicles rear curb height by measuring the distance from both rear frame rails to top edge of Vehicle Height Checking Fixture.
16. If, after setting the vehicle to the specified design height using the required procedure, curb height specification still is not obtained, coil spring preload will need to be adjusted to obtain correct vehicle curb height.
17. Remove the vehicle height checking fixtures from the vehicle.