Caster and Camber Adjustment
GENERAL INFORMATIONThe camber and caster angles on the Viper are adjustable using cams located on the lower control arm bushing pivot bolts. Correct camber and caster specifications are obtained by simultaneously rotating front and rear adjustment cams until lower control arm is correctly positioned.
CAUTION: Prior to any cam bolt rotation, locknuts must be loosened to ends of pivot bolt threads. This must be done to allow lower control arm mounting brackets to be spread, allowing free movement of bushings. If not done, serious bracket bending, weld breakage of cam retainer, free cam and cam bolt shank fracturing, or thread damage can occur. It may be necessary to tap bracket ears away from bushings to allow unrestricted cam bolt movement.
INCLINOMETER SETUP FOR CASTER ANGLE VIEWING
Inclinometers Installed On DRB III:
Rear Caster Angle Fixture:
Front Caster Angle Fixture:
Both front and rear caster angle on the Viper is read. This is accomplished by reading caster directly off the front and rear knuckles through inclinometer sensors attached to the DRB III scan tool, rather than using the alignment machine's sweep method. Use Special Tools 6989, 6996, 6915, and 6916 which are included in the 96 Essential Viper Alignment Package.
NOTE: It is necessary to have a DRB III with an attached PEP module capable of reading inclinometers.
Cable Connections At DRB III:
1. Plug the cable from the switch box, Special Tool 6996 or equivalent, into the pep module connector on the DRB III marked "INCL".
2. Plug the power cable (supplied with the DRB III kit) into the DRB III power connector marked "VEHICLE".
3. Attach the two inclinometers, Special Tool 6989 or equivalent, to the switch box. Only two inclinometers are supplied and should be used as a pair to measure either rear caster or front caster, one at a time.
4. Attach the power cable from the DRB III to the vehicle data connector.
5. Select the Stand Alone DRB III option from the Main Menu screen.
6. Select the Inclinometer option from the Stand Alone Main Menu.
7. Select the Read/Display Angle option from the Inclinometer Main Menu. This option is used to zero the inclinometers before use on the vehicle. The inclinometer, Special Tool 6989 or equivalent, must be zeroed (calibrated) prior to each time it will be used to read the caster angle on the vehicle. This screen shows the readout for the left and right inclinometers.
8. Press F3 to show both inclinometers.
Zero The Inclinometers:
9. Zero the inclinometers: Place both inclinometers together on a known flat, level surface, such as the alignment rack, with the knurled ends of the fastening screws facing upward. Press F2. This zeros the inclinometers in one direction. Rotate the inclinometers 180 degrees in place, then press F2 again to zero both inclinometers in the other direction. The inclinometers are now ready to be installed on the vehicle.
10. Mount inclinometers to either both rear or both front Caster Angle Fixtures, Special Tool 6916 or 6915. Make sure the inclinometer from the left side of the switch box is mounted to the left fixture and the inclinometer from the right side of the switch box is mounted to the right fixture.
Rear Caster Angle Fixture Installed On Knuckle:
Front Caster Angle Fixture Installed On Knuckle:
11. Once inclinometers are mounted on Caster Angle Fixtures, they can be mounted on either the rear or front knuckle caster angle pads as shown. The caster pads are located on the front edge of the front steering knuckle and the rear edge of rear knuckle. Be sure caster pads are thoroughly cleaned before mounting the Caster Inclinometers on the knuckles. Caster Inclinometers must sit flat on caster pads to obtain accurate caster readings.
12. Adjust caster using the measurements viewed on the DRB III screen, and camber using the measurements viewed on the alignment equipment.
13. When adjustments are complete, transfer the inclinometers to the other set of fixtures to measure front or rear caster which has yet to be measured.
CAMBER ANGLE
Camber angle adjustment involves the repositioning of the lower control arm pivot bolts using the adjustment cams. There are 2 cams located on each lower control arm pivot bolt, 4 per each corner of the vehicle front and rear. Repositioning of the pivot bolt cams moves the lower ball joint in or out to obtain the required camber specifications.
CASTER ANGLE
Caster angle adjustment, like camber angle adjustment, involves the repositioning of the lower control arm pivot bolts using the adjustment cams. There are 2 cams located on each lower control arm pivot bolt, 4 per each corner of the vehicle front and rear. Repositioning of the pivot bolt cams moves the lower ball joint fore or aft as required to obtain the required caster specifications.