GM Buick/Oldsmobile/Pontiac/Full-Size 1975-1990 Repair Guide

Lower Ball Joints


See Figures 1 and 2


Before performing this inspection, make sure the wheel bearings are adjusted correctly and that the control arm bushings are in good condition.

All models covered in this guide are equipped with wear indicators on the lower ball joint. As long as the indicator extends below the ball stud seat, replacement is unnecessary; if only the lower ball joint is bad, however, both upper and lower ball joints should be replaced.

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Fig. Fig. 1: Lower ball joint wear indicator


  1. Raise the vehicle and support it securely. Support the lower control arm with a jack or jackstand. Remove the wheel.
  3. Remove the lower ball stud cotter pin, and loosen the ball stud nut 2-3 turns.
  5. Install a special tool designed for such work between the two ball studs, and press the stud downward in the steering knuckle to free it. Then, remove the stud nut.
  7. Guide the lower control arm out of the opening in the splash shield with a putty knife or something similar. Lift up on the upper control arm and place a block of wood between it and the frame. Be careful not to put tension on the brake hose as you do this.
  9. Remove the ball joint seal by prying off the retainer with a prybar or driving it off with a chisel.
  11. Remove grease fittings and install a tool designed for this purpose and press the ball joint out of the lower control arm. On some models, you may have to disconnect the tie rod at the knuckle to do this.

To install:
  1. Position the ball joint in the control arm so that the grease purge on the seal faces inboard. Press the joint in with a tool designed for this purpose until it bottoms on the control arm. Remove the block of wood and then insert the ballstud through the steering knuckle hole on the control arm.
  3. Turn the ball stud cotter pin hole so it faces fore and aft. Install the nut on the ball stud and torque it to: 105 ft. lbs. (140 Nm) on 1975-77 vehicles; 83 ft. lbs. (112 Nm) on 1978-79 vehicles; 90 ft. lbs. (122 Nm) on 1980-81 vehicles; 70 ft. lbs. (95 Nm) on 1982-83 models; and 90 ft. lbs. (122 Nm) on 1984-90 models. Then, as necessary, turn the nut tighter to line up one of the castellations with the cotter pin hole. Finally, install the cotter pin and bend both prongs down and back against the nut. Lubricate the joint until grease appears at the seal. Remove supports and lower the vehicle.

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Fig. Fig. 2: Pressing out the lower ball joint