Replacement of rear shock absorber upper mounting bushings and hardware on a 1966 Corvette with independent rear suspension.

Warnings

Tools required

Parts

• Rear shock absorber upper mounting bushing kit × 2 — Use OEM specification or equivalent (includes rubber bushings and retaining washers)
• Upper shock mount retaining nuts (7/16"-20) × 2 — Grade 5 or better
• Anti-seize compound × 1 — Standard copper or nickel-based

Preparation

1. Park vehicle on level, solid ground and engage parking brake firmly.
2. Place wheel chocks in front of both front tires.
3. If shock mounts are severely corroded, apply penetrating oil to upper shock mount nuts and allow to soak for 30 minutes before beginning work.
4. Loosen rear wheel lug nuts while vehicle is on the ground.
5. Raise rear of vehicle using floor jack at the differential carrier housing (not under the shock absorbers or trailing arms).
6. Place jack stands under the frame rails just forward of the rear suspension mounting points. Lower vehicle onto jack stands.
7. Remove rear wheels and set aside.
8. Verify vehicle stability by gently pushing on rear quarter panel before working underneath.

Procedure

1. 1

   Access upper shock mount from trunk
   The 1966 Corvette rear shock upper mount attaches to a frame-mounted bracket and is serviced from beneath the vehicle, NOT through the trunk floor. Raise and support the vehicle, then locate the upper shock mounting stud/bolt at the frame bracket near the top of each rear shock.
2. 2

   Inspect upper mount condition
   Examine the upper shock mount from above. Note the condition of the rubber bushing, the shock shaft threads, and the frame mounting surface. Look for rust, damage, or deformation of the frame mounting area. If the frame is cracked or severely corroded around the shock mount hole, the repair is beyond the scope of this procedure and requires frame repair.
3. 3

   Support lower shock body
   Working from below the vehicle, use a floor jack or tall jack stand to support the lower shock body and trailing arm assembly. Place the jack pad under the trailing arm near the shock mounting point. Raise until there is slight upward pressure, just enough to relieve tension on the upper shock mount but not enough to compress the shock significantly. This prevents the shock from dropping when the upper mount is removed.
4. 4

   Remove upper shock mount retaining nut
   Working from beneath the vehicle, hold the upper shock stud/shaft flats (if present) and remove the upper shock mount retaining nut using the correct-size socket or wrench (verify fastener size against the FSM). Remove the retaining nut, washer, and upper rubber bushing. Note the order and orientation of all components for reassembly.
5. 5

   Lower shock shaft through frame
   Working from below, carefully lower the floor jack supporting the trailing arm. This will allow the shock shaft to drop down through the frame mounting hole. Lower slowly and watch for the shock shaft to clear the frame completely. The shock body will now hang from the lower mounting point only.
6. 6

   Remove old lower bushing and inspect
   The lower rubber bushing typically remains on the shock shaft or in the frame mounting hole. Remove it by hand or with a pry bar if stuck. Inspect the shock shaft threads for damage, corrosion, or stripped threads. Clean the threads with a wire brush. Inspect the frame mounting hole for sharp edges, rust, or damage that could cut the new rubber bushing.
7. 7

   Clean mounting surfaces
   Using a wire brush, thoroughly clean the frame mounting surface around the shock mount hole from both above (trunk side) and below. Remove all rust, old rubber residue, and debris. If any threaded fasteners are damaged, clean and chase them with the correct tap matching the original fastener thread (verify thread size and pitch against the actual hardware and FSM). Wipe surfaces clean with a rag.
8. 8

   Install new lower bushing on shock shaft
   Slide the new lower rubber bushing onto the shock shaft from below. The bushing should have a tapered or cupped design; install with the wider end facing up toward the frame (the bushing compresses upward into the frame mounting hole). If the bushing is symmetrical, either orientation is acceptable but note the original configuration.
9. 9

   Raise shock shaft through frame mount
   Using the floor jack, raise the trailing arm and shock assembly until the shock shaft extends up through the frame mounting hole and protrudes into the trunk area. The lower rubber bushing should seat against the underside of the frame. Continue raising until the shock shaft extends approximately 0.5 to 1 inch above the frame mounting surface in the trunk.
10. 10

    Install upper bushing and washer
    From inside the trunk, slide the upper rubber bushing over the shock shaft. Orient the bushing so the cupped or tapered side faces down into the frame hole, matching the lower bushing orientation. Place the metal retaining washer on top of the upper bushing. The washer should be large enough to capture the bushing and prevent it from pulling through under compression.
11. 11

    Install and torque retaining nut
    Apply a light coating of anti-seize compound to the shock stud threads. Thread the new retaining nut on by hand. Once hand-tight, hold the shock to prevent rotation and torque the retaining nut to the factory specification (verify exact value in the 1966 Corvette Shop Manual; do not rely on an estimated figure). Do not overtighten, as this can crush the rubber bushings and cause premature failure. Do not overtighten, as this can crush the rubber bushings and cause premature failure. The bushing should be compressed but not completely flattened.
12. 12

    Verify shock alignment and travel
    With the upper mount secured, slowly lower the floor jack supporting the trailing arm. The shock should compress and extend smoothly without binding. Bounce the rear suspension by pushing down on the frame rail and observe shock operation. The shock shaft should remain centered in the frame mounting hole with no contact between metal components. If contact occurs, check bushing installation and alignment.
13. 13

    Repeat for opposite side
    Repeat steps 1 through 12 for the opposite rear shock absorber. Ensure both sides are torqued to the same specification and both shock mounts are properly seated.

Reassembly

1. Reinstall any trunk access panels or cover plates that were removed.
2. Replace trunk mat or carpeting.
3. Reinstall rear wheels and hand-tighten lug nuts in a star pattern.
4. Raise vehicle slightly with floor jack, remove jack stands, and lower vehicle to the ground.
5. Torque wheel lug nuts to 70-80 ft-lb in a star pattern with wheels on the ground.

Verification

• With vehicle on the ground, bounce each rear corner and verify shock absorbers are functioning (vehicle should settle after 1-2 bounces without continued oscillation).
• Inspect upper shock mounts from trunk to verify no movement or play in the mounting hardware.
• Test drive vehicle at low speed in a safe area and verify no unusual noises, vibrations, or handling issues from rear suspension.
• After 50-100 miles of driving, re-check upper shock mount retaining nut torque from inside trunk to ensure nuts have not loosened.
• Visually inspect shock shafts for any contact marks on the frame mounting holes, which would indicate misalignment or improper bushing installation.

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