Curb Height Checking and Setting

Viper alignment specifications must be checked, and all alignment adjustments made with the vehicle at its required curb height specification.
1. Correctly position the vehicle on alignment equipment per the equipment manufacturer's recommendations.
2. Check all tires for proper inflation pressure and adjust as necessary.

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 Height Checking Fixtures:

Vehicle Front Height Checking Fixture Installed:

Vehicle Rear Height Checking Fixture Installed:

3. Install front and rear Vehicle Height Checking Fixtures, Special Tool 6914, at the base of both inner rim flanges of the front and rear wheels as shown.

Height Checking Fixture Installation On Wheel:

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

Measuring Vehicle Front Curb Height:

5. Check the distance from each of the front frame rails to the top surface of the Vehicle Height Checking Fixture, Special Tool 6914, (at front edge).

Measuring Vehicle Rear Curb Height:

6. Check distance from both rear frame rails to top edge of Vehicle Height Checking Fixture, Special Tool 6914.

NOTE: Vehicle curb height on the Viper can be affected if all rubber bushings used in the vehicles suspension are not tightened and torqued with vehicle at DESIGN HEIGHT. This is due to the extreme stiffness of the rubber used in the suspension component bushings. Use the following procedure to ensure all bushings are torqued to specifications with the vehicle set to its specified design height.

7. If vehicle does not meet curb height specifications, loosen all bolts on rubber bushings of suspension components, and shock absorber mounting bolts. Correctly ballast or jack vehicle to obtain the specified vehicle design height. While vehicle is at specified design height, tighten and torque to specification, all suspension component fasteners previously loosened. Remove all ballast and jacking equipment from vehicle, then check vehicle curb height again to see if it meets specifications.
8. If vehicle still does not meet vehicle curb height specifications, inspect following suspension components of vehicle for conditions which may cause vehicle to not meet vehicle curb height specifications:
- Shock absorber assembly mounting bushings.
- Upper and lower control arm mounting bushings.
- Shock absorber springs.
- Frame damage to vehicle which affects mounting location of a suspension component.
- Front and rear sway bar.
- Inspect all suspension components for signs of damage.
9. If vehicle and/or component inspection does not determine a cause as to why vehicle is not meeting front or rear curb height specification, coil springs on the shock absorber assemblies can be shimmed, or have a reduced height spring seat installed. The shim, or reduced height spring seat installation should allow vehicle to be set to correct curb height specification.If shock absorber springs require shimming, or installation of reduced height spring seats, both shock absorbers on that end of the vehicle requiring height adjustment, must be serviced the same. When shimming shock absorber springs, or installation of reduced height spring seats, is required, see Shock Absorber Replacement for correct shock absorber removal and installation procedure.

NOTE: After shock absorber springs have been shimmed, or reduced height spring seats have been installed, and shock absorbers have been installed back on the vehicle, vehicle must be ballasted or jacked to the specified vehicle design height before tightening and torquing the shock absorber mounting bolts.

10. Remeasure curb height.
11. Remove the vehicle height checking fixtures from the vehicle.