Curb Height Measurement

NOTE: The Viper front and rear wheel alignment must be checked and or adjusted to the preferred specifications, with the vehicle at CURB HEIGHT rather than at DESIGN HEIGHT.

1. Correctly position the vehicle on alignment equipment per the alignment equipment manufacturer's recommendations.
2. Check that all tires are at the preferred inflation pressure and adjust as necessary if they are not.

NOTE: When the front and rear height checking fixture is installed on the wheels, they must be positioned at the very bottom of the wheel inner flange. 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 curb height measurement.











3. Install the front and rear Vehicle-Height Checking Fixtures, Special Tools 6914, or equivalent on the inner bead of the front and rear rims.





4. Refer to illustration to ensure that the Vehicle Height Checking Fixtures, Special Tool 6914, or equivalent are correctly attached to the inner flange of the front and rear wheels.

CAUTION: When jouncing vehicle suspension, do not allow frame of vehicle to hit against the front or rear height checking fixtures. If weight of vehicle contacts height checking fixture, fixture could bend, thus affecting accuracy of curb height measurement and setting of the vehicle's design height.

5. 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.





6. Check the distance from both front frame rails to the top surface of Vehicle Height Checking Fixture, (at front edge).





7. Check distance from both rear frame rails to top edge of Vehicle Height Checking Fixture.

NOTE: If vehicle is within required curb height specification, proceed to step Step 10 of the vehicle alignment procedure.

NOTE: If the vehicle is not within the required curb height specification range, do not perform a front or rear wheel alignment procedure. The vehicle MUST be within the required curb height specification to obtain an accurate wheel alignment. Refer to the information below, for causes of incorrect vehicle curb height and the procedures used for setting a vehicle to its correct curb height specification.

8. Vehicle curb height on the Viper can be extremely affected if all rubber bushings used in the vehicles suspension are not tightened and torqued with vehicle at specified design height. This is due to the extreme stiffness of the rubber bushings used in the vehicle's suspension components. Refer to, Setting Vehicle To Design Height. This will ensure all bushings are tightened and torqued to specifications, with the vehicle set to its specified design height. Then check vehicle curb again to verify it is within specification, before performing vehicle alignment procedure.
9. If after setting vehicle to specified design height using required procedure, curb height specification still is not obtained, coil spring preload will need to be adjusted to obtain correct vehicle curb height. Refer to the Shock Absorber.





10. Attach alignment equipment heads onto the vehicle wheels. The Viper uses flangeless style wheels, thus any alignment equipment used must be capable of attaching to outside edge of wheel bead lip.