Strut Bearing

Replace the upper strut mount bearings on a 1966 Corvette, which uses a non-strut independent front suspension system with upper control arm bushings that may be referred to colloquially as 'strut bearings'.

Warnings

Tools required

Parts

• Upper control arm bushing kit (both sides) × 2 — Use OEM specification or Moog K6137
• Upper ball joint (if worn) × 2 — Use OEM specification or Moog K6136
• Cotter pins (1/8" x 1.5") × 4 — Standard 1/8" castle nut cotter pins

Preparation

1. Park vehicle on level, solid surface and set parking brake firmly
2. Place wheel chocks behind rear wheels
3. Loosen front wheel lug nuts while vehicle is on ground (do not remove)
4. Raise front of vehicle with floor jack at factory jacking points on frame
5. Place jack stands under frame rails behind front crossmember at solid contact points
6. Lower vehicle onto jack stands and verify stability before proceeding
7. Remove front wheels completely
8. Spray all suspension fasteners with penetrating oil and allow to soak
9. Mark the position of upper control arm shaft relative to frame bracket using paint pen for reference during reinstallation

Procedure

1. 1

   Support the lower control arm
   Position a floor jack under the lower control arm spring seat to support the coil spring tension. Raise jack just enough to make contact and take the load - do not lift the suspension. The jack must remain in place throughout the procedure to control spring compression.
2. 2

   Remove upper ball joint castle nut
   Remove the cotter pin from the upper ball joint castle nut. Using a 7/16" socket, remove the castle nut from the upper ball joint stud at the steering knuckle. Do not allow the ball joint stud to spin - hold it with a 3/8" Allen key if necessary.
3. 3

   Separate upper ball joint from knuckle
   Use a ball joint separator or pickle fork to break the taper fit between the upper ball joint stud and the steering knuckle. Strike the separator sharply with a hammer until the stud releases. If reusing the ball joint, avoid using a pickle fork as it can damage the boot - use a proper ball joint separator tool instead.
   ⚠The knuckle may drop suddenly when the ball joint separates. Keep hands and body clear of the assembly.
4. 4

   Remove shock absorber upper mounting
   Access the shock absorber upper mounting nuts through the engine compartment. Remove the 2 upper shock mounting nuts using a 1/2" socket. The shock will remain attached at the lower mount.
5. 5

   Remove upper control arm shaft nuts
   Locate the upper control arm shaft mounting bolts that pass through the frame brackets. These are accessible from inside the engine compartment. Remove the 2 nuts from the front shaft bolt and the 2 nuts from the rear shaft bolt using a 9/16" socket. Hold the bolt heads with a wrench to prevent spinning.
6. 6

   Remove upper control arm assembly
   Carefully withdraw the 2 upper control arm shaft bolts from the frame brackets. The upper control arm assembly with bushings can now be removed from the vehicle. Note the position and orientation of any shims present between the control arm shaft and frame bracket - these control caster and camber. Keep shims organized by location for reinstallation.
7. 7

   Remove old bushings from control arm
   With the upper control arm on a bench, use a control arm bushing removal tool or a C-clamp with appropriate sized sockets to press out the old bushings from the control arm shaft sleeves. The bushings are press-fit and will require substantial force. Press from the inner sleeve outward.
8. 8

   Clean control arm shaft bores
   Thoroughly clean the bushing bores in the control arm shaft sleeves using a wire brush and solvent. Remove all rust, old rubber, and debris. Inspect the shaft sleeves for cracks, elongation, or damage. Replace the entire control arm if shaft sleeves are damaged.
9. 9

   Install new bushings
   Apply a thin film of soapy water or bushing installation lubricant to the outer sleeve of the new bushings (never use petroleum-based lubricant). Orient the bushing correctly - the void or slit in the bushing must align perpendicular to the direction of control arm travel. Press the new bushings into the control arm shaft sleeves using a C-clamp or press and appropriate sized mandrels until fully seated and flush with the sleeve ends.
10. 10

    Reinstall upper control arm to frame
    Position the upper control arm with new bushings back into the frame brackets. Reinstall any shims in their original positions and orientation. Insert the 2 shaft bolts through the frame brackets and control arm bushings. Thread on the nuts finger-tight but do not torque yet - suspension must be at ride height before final torque.
11. 11

    Reconnect upper ball joint to knuckle
    Raise the floor jack under the lower control arm to bring the steering knuckle up to meet the upper ball joint stud. Guide the upper ball joint stud through the hole in the top of the steering knuckle. Thread on the castle nut and tighten to 50 ft-lb. Continue tightening only enough to align the castle nut slots with the stud hole, then install a new cotter pin and bend the ends.
12. 12

    Reinstall shock absorber upper mount
    Reconnect the shock absorber upper mounting studs to the frame. Install the 2 upper mounting nuts and tighten to 8-10 ft-lb.
13. 13

    Load suspension to ride height
    Using the floor jack under the lower control arm, carefully raise the suspension until the vehicle just begins to lift off the jack stands. This simulates normal ride height and loads the bushings. In this position, the control arm bushings are at their neutral position and ready for final torque.
14. 14

    Torque upper control arm shaft nuts
    With the suspension at ride height, torque the upper control arm shaft nuts to 55 ft-lb. Torque both the front and rear shaft nuts. Do not torque these fasteners with the suspension hanging free or bushing life will be severely reduced.
15. 15

    Lower vehicle and complete opposite side
    Lower the floor jack from under the control arm. Reinstall the wheel and thread on lug nuts finger-tight. Repeat the entire procedure for the opposite side front suspension. After both sides are complete, lower the vehicle to the ground and torque wheel lug nuts to 80 ft-lb in a star pattern.

Reassembly

1. Ensure all fasteners are properly torqued per the procedure
2. Verify all cotter pins are installed and properly bent
3. Confirm shock absorber mounting hardware is secure
4. Double-check that wheel lug nuts are torqued to specification

Verification

• With vehicle on ground, bounce each front corner firmly and listen for any unusual noises or looseness
• Verify steering knuckle has no vertical play when grasping the top of the tire
• Inspect all work areas to ensure no tools or parts were left in the suspension
• Test drive in a safe area at low speed and verify normal steering response and no pulling
• Schedule a professional front-end alignment immediately - do not delay as the alignment was disturbed by this procedure

More procedures for this vehicle