This procedure covers removal and replacement of the lower control arm on a 1970 AMC Rebel Machine, including disconnection of ball joint and bushing mounts.

Warnings

Tools required

Parts

• Lower control arm assembly × 1 — Use OEM specification or quality aftermarket
• Lower ball joint (if not included with control arm) × 1 — Use OEM specification
• Control arm bushing set × 1 — Use OEM specification or polyurethane upgrade
• Cotter pins × 3 — Various sizes for ball joint and tie rod

Preparation

1. Park vehicle on level, solid surface and set parking brake firmly
2. Place wheel chocks behind rear wheels
3. Loosen lug nuts on the wheel where lower control arm will be replaced (do not remove yet)
4. Apply penetrating oil to all suspension fasteners and ball joint taper fit, allow to soak for 15-30 minutes
5. Raise front of vehicle with floor jack at factory jacking point on frame rail
6. Install jack stands under frame rails on both sides for stability
7. Remove wheel and tire assembly completely

Procedure

1. 1

   Support the lower control arm
   Position a floor jack under the lower control arm near the ball joint to support the weight of the arm and compressed coil spring. Raise jack just enough to slightly compress the spring and take load off the control arm mounting bolts. This is critical for safe disassembly.
2. 2

   Disconnect shock absorber lower mount
   Remove the lower shock absorber mounting bolt and nut that attaches the shock to the lower control arm. On the Rebel Machine, this is typically a 9/16" or 5/8" bolt. Swing the shock absorber up and out of the way, securing it with wire if necessary to prevent damage to brake lines.
3. 3

   Remove stabilizer bar link
   If equipped with front stabilizer bar, disconnect the link from the lower control arm by removing the nut, bolt, and bushings. Note the order and orientation of bushings and washers for reassembly. The stabilizer link typically uses a 1/2" or 9/16" fastener on this model.
4. 4

   Remove cotter pin and castle nut from ball joint
   Straighten and remove the cotter pin from the lower ball joint castle nut using pliers or a pick tool. Remove the castle nut completely using the appropriate socket (typically 13/16" or 7/8" on AMC applications). Do not remove the jack support yet.
5. 5

   Separate ball joint from steering knuckle
   Using a ball joint separator tool (pickle fork or puller-type), separate the lower ball joint taper from the steering knuckle. Position the separator between the control arm and knuckle, then drive or press the taper loose. Once free, carefully lower the jack slightly to relieve spring tension while supporting the control arm. The steering knuckle will pivot upward on the upper ball joint.
6. 6

   Remove front control arm pivot bolt
   Locate the front pivot bolt that secures the control arm to the frame crossmember. This bolt passes through the front bushing and is typically a 3/4" bolt head. Remove the nut from the inboard side using a wrench or socket, then drive out the bolt. You may need to use a brass drift and hammer if the bolt is seized in the bushing.
7. 7

   Remove rear control arm pivot bolt
   Remove the rear pivot bolt and nut that secures the rear bushing mount to the frame bracket. This is also typically a 3/4" fastener. Support the control arm with one hand as you remove this final bolt, as the arm will be free to drop once the bolt is removed.
8. 8

   Remove lower control arm assembly
   With both pivot bolts removed and the ball joint disconnected, carefully lower and remove the control arm from the vehicle. The coil spring will remain captured between the upper control arm pocket and the frame spring seat. Maneuver the control arm out from behind the spring and brake assembly.
9. 9

   Inspect and prepare replacement control arm
   Clean the mounting areas on the frame and crossmember with a wire brush. Inspect the coil spring for damage or cracking. If installing a new control arm with bushings already pressed in, verify bushings are properly oriented. If reusing the control arm, inspect bushings for wear and replace if necessary using a bushing press. Install new ball joint if not already included with replacement arm.
10. 10

    Install replacement control arm
    Position the new or rebuilt lower control arm into place, maneuvering it behind the brake assembly and into alignment with the frame mounting brackets. Align the front and rear bushing holes with the mounting points on the frame and crossmember.
11. 11

    Install pivot bolts loosely
    Insert the front and rear pivot bolts through the frame brackets and control arm bushings. Thread the nuts onto the bolts by hand, but do not tighten yet. Leave the fasteners loose enough to allow the control arm to pivot. This is critical because suspension bushings must be torqued at ride height to prevent premature failure.
12. 12

    Connect ball joint to steering knuckle
    Use the floor jack to raise the lower control arm, compressing the coil spring and aligning the ball joint stud with the hole in the steering knuckle. Insert the ball joint stud through the knuckle and thread the castle nut onto the stud. Tighten the castle nut until snug, then continue tightening to the next castle slot that aligns with the cotter pin hole in the stud. Install a new cotter pin and bend the ends to secure.
13. 13

    Reconnect stabilizer bar and shock absorber
    Reconnect the stabilizer bar link to the lower control arm using new or existing hardware, ensuring bushings are properly positioned. Install and tighten the lower shock absorber bolt and nut. These fasteners can be fully tightened at this time as they do not pass through rubber bushings.
14. 14

    Lower vehicle to load suspension
    Install the wheel and tire assembly and snug the lug nuts. Remove the jack stands and carefully lower the vehicle until the suspension is at normal ride height with tires on the ground, but keep enough jack pressure to prevent the vehicle from rolling. This loads the suspension bushings in their normal operating position.
15. 15

    Torque all fasteners to specification
    With the vehicle at ride height, torque the front and rear control arm pivot bolt nuts to factory specification (typically 75-100 ft-lbs for AMC applications, verify with factory service manual). Torque wheel lug nuts to specification (typically 75-85 ft-lbs) in a star pattern. Verify all other fasteners are properly tightened including ball joint castle nut, shock mount, and stabilizer link.

Reassembly

1. Always torque control arm bushing bolts at ride height to prevent bushing bind and premature wear
2. New cotter pins must be used on all castellated nuts; never reuse old cotter pins
3. If camber or caster adjustments are available on this model year, alignment should be checked after control arm replacement
4. Road test vehicle at low speed and verify no unusual noises or handling issues before returning to normal service

Verification

• Verify all fasteners are torqued to specification and properly secured with cotter pins where applicable
• Check that steering moves freely through full range of motion without binding or interference
• Bounce the front end of the vehicle and verify no abnormal noises from the suspension
• Have front end alignment checked and adjusted by a qualified shop, as control arm replacement affects camber and caster settings
• Test drive vehicle at low speed and verify proper handling and no pulling to either side

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