This procedure covers the removal and replacement of the rear trailing arm (control arm) on a 1966 Chevrolet Corvette with independent rear suspension.

Warnings

Tools required

Parts

• Trailing arm (control arm) × 1 — Use OEM specification or aftermarket equivalent
• Trailing arm bushings (if not included with arm) × 2 — Use OEM specification
• Trailing arm to spindle support bolts × 2 — Use OEM specification
• Trailing arm to frame bracket bolts × 2 — Use OEM specification
• Cotter pins × 2 — 1/8 inch diameter

Preparation

1. Park vehicle on level surface and apply parking brake.
2. Chock front wheels securely.
3. Loosen rear wheel lug nuts while vehicle is on ground.
4. Raise rear of vehicle and support on jack stands placed under frame rails, not under suspension components.
5. Remove rear wheel on side being serviced.
6. Spray all fasteners to be removed with penetrating oil and allow to soak.
7. Visually inspect trailing arm, bushings, and mounting points for damage or excessive wear.

Procedure

1. 1

   Support the differential and halfshaft assembly
   Position a transmission jack or sturdy adjustable jack stand under the differential carrier to support the weight of the differential and halfshaft. Raise just enough to take the load off the trailing arm but do not lift the suspension. The differential must remain supported throughout the entire procedure.
2. 2

   Disconnect the shock absorber lower mount
   Locate the shock absorber lower mounting bolt at the trailing arm. Using a 15/16 inch socket and wrench, remove the lower shock mounting bolt and washer. Swing the shock absorber up and out of the way. Some resistance is normal due to shock compression.
3. 3

   Remove the rear strut rod
   The strut rod runs from the trailing arm forward to the front mounting bracket on the differential carrier. Using a 15/16 inch socket, remove the bolt securing the strut rod to the trailing arm bracket. Then remove the front mounting bolt from the differential carrier bracket. Remove the strut rod assembly. Note the position and number of any washers or shims for reinstallation.
4. 4

   Disconnect the camber control rod
   Locate the camber control rod (upper control rod) connecting the trailing arm to the frame bracket. Remove the cotter pin from the castle nut at the trailing arm end. Using a 1 inch socket, remove the castle nut. Use a ball joint separator or pickle fork to separate the camber rod ball joint from the trailing arm. Some force will be required. Remove the frame bracket mounting bolt using a 1 inch socket and remove the camber rod assembly.
5. 5

   Mark the transverse spring position
   Before disturbing the spring, use a paint pen or chalk to mark the position of the trailing arm relative to the transverse leaf spring carrier. This will aid in reassembly alignment. Note the position of the spring pad on the trailing arm.
6. 6

   Release tension on transverse leaf spring
   Carefully lower the transmission jack supporting the differential slightly to relieve tension on the transverse leaf spring where it contacts the trailing arm. Lower only enough to create clearance between the spring and the trailing arm spring pad (approximately 1-2 inches). Monitor the spring to ensure it does not shift suddenly.
   ⚠️The transverse spring is under significant load. Lower the jack very slowly and be prepared to stop if the spring begins to shift unexpectedly.
7. 7

   Disconnect the trailing arm from spindle support
   Locate the two bolts securing the trailing arm to the spindle support (hub carrier). These are accessed from the rear of the assembly. Using a 1-1/8 inch socket and wrench, remove both bolts and lock washers. The spindle support will now be free from the trailing arm but should remain supported by the halfshaft and brake components. Do not allow the spindle to hang unsupported.
8. 8

   Remove trailing arm front pivot bolts
   Locate the two bolts securing the trailing arm to the frame mounting bracket at the front pivot point. These bolts pass through the trailing arm bushings. Using a 1 inch socket and breaker bar, remove both pivot bolts. These bolts may be extremely tight and corroded. Apply additional penetrating oil if necessary and use heat carefully if bolts will not break free.
9. 9

   Remove the trailing arm
   With all fasteners removed, carefully maneuver the trailing arm out from between the frame bracket and the spindle support. The arm may need to be rotated and angled to clear the spring and other components. Inspect the removed arm for cracks, bends, or other damage. Check the frame bracket and spindle support mounting surfaces for damage or elongated holes.
10. 10

    Inspect and prepare bushings
    If the new trailing arm does not include pre-installed bushings, press or drive the old bushings out of the removed arm to use as reference for orientation. Clean the bushing bores in the new trailing arm thoroughly with a wire brush. Install new bushings in the correct orientation (bushings are typically offset or directional). Lubricate bushing outer surface lightly with soapy water or rubber lubricant before installation if pressing in by hand.
11. 11

    Install the new trailing arm
    Position the new trailing arm into place, aligning the front pivot bushing eyes with the frame bracket holes. Insert the front pivot bolts through the frame bracket and bushings but do not tighten fully yet. Thread nuts onto bolts hand-tight only. The bushings must be torqued at ride height to prevent premature failure.
12. 12

    Connect trailing arm to spindle support
    Align the rear of the trailing arm with the spindle support mounting holes. Install the two mounting bolts with lock washers and thread hand-tight. You may need to use a pry bar to align holes perfectly. Once aligned, tighten these bolts in a cross pattern to ensure even seating.
13. 13

    Reconnect the transverse leaf spring
    Slowly raise the transmission jack supporting the differential until the transverse leaf spring makes contact with the trailing arm spring pad. Align the spring with the marks made during disassembly. Continue raising until the suspension reaches approximately ride height position. The spring should seat fully into the spring pad on the trailing arm.
14. 14

    Reinstall the camber control rod
    Position the camber control rod between the frame bracket and the trailing arm. Install the frame bracket mounting bolt and tighten securely. Insert the ball joint stud into the trailing arm and install the castle nut. Tighten the castle nut and install a new cotter pin through the castle nut slots and ball joint stud. Bend cotter pin ends to secure.
15. 15

    Reinstall the strut rod
    Position the strut rod between the trailing arm bracket and the differential carrier bracket. Install any shims or washers noted during removal in their original positions. Install both mounting bolts and tighten the differential carrier end first, then the trailing arm end. This maintains proper geometry.
16. 16

    Reconnect the shock absorber
    Swing the shock absorber back into position and align the lower mounting eye with the trailing arm bracket. Install the lower shock mounting bolt with washer and tighten securely. Ensure the shock moves freely through its travel without binding.
17. 17

    Torque all fasteners to specification
    With the vehicle still supported on jack stands and the suspension at approximately ride height (differential jack still supporting weight), torque all fasteners. Due to lack of factory specifications in the database, use accepted standards for Grade 8 fasteners of the sizes involved: trailing arm pivot bolts to 95-105 ft-lb, trailing arm to spindle support bolts to 75-85 ft-lb, strut rod bolts to 50-60 ft-lb, camber rod castle nut to 35-40 ft-lb (then advance to next cotter pin slot if needed), and shock mounting bolt to 65-75 ft-lb. Pivot bushings must be torqued at ride height to prevent premature wear.
18. 18

    Final inspection and wheel installation
    Remove the transmission jack from under the differential. Visually inspect all connections to ensure fasteners are tight and properly installed. Check that no tools or parts were left in the suspension area. Reinstall the wheel and hand-tighten lug nuts in a star pattern. Lower the vehicle to the ground and torque lug nuts to 80 ft-lb in a star pattern.

Reassembly

1. All suspension bushings must be torqued at ride height (vehicle weight on wheels or suspension supported at normal ride height) to prevent premature bushing failure.
2. If the vehicle has not had an alignment recently, a four-wheel alignment is mandatory after trailing arm replacement.
3. Road test the vehicle at low speeds initially to verify proper suspension operation and listen for any unusual noises before normal operation.

Verification

• Verify all fasteners are tight and properly torqued.
• Check that all cotter pins are installed and properly bent.
• Verify shock absorber is securely mounted and moves freely.
• Confirm transverse spring is properly seated in the trailing arm spring pad.
• Test drive at low speed and verify no unusual noises, vibrations, or handling issues.
• Schedule four-wheel alignment within 50 miles of completion.

More procedures for this vehicle