Remove and replace the upper control arm on a 2023 Chevrolet Bolt EUV, including disconnection of the ball joint and control arm mounting bolts.

Warnings

Tools required

Parts

• Upper control arm assembly × 1 — Use OEM specification
• Cotter pin × 1 — Use OEM specification

Preparation

1. Park vehicle on level surface and engage parking brake
2. Loosen wheel lug nuts while vehicle is on ground, but do not remove
3. Raise vehicle with floor jack at manufacturer-approved lift point
4. Support vehicle securely on jack stands at designated support points
5. Remove wheel and tire assembly completely
6. Inspect upper control arm for damage and verify replacement is necessary

Procedure

1. 1

   Remove ball joint cotter pin
   Locate the upper ball joint nut where the control arm connects to the steering knuckle. Use needle nose pliers to straighten and remove the cotter pin from the ball joint castle nut. Discard the old cotter pin as a new one must be installed during reassembly.
2. 2

   Loosen ball joint nut
   Using an 18mm socket, loosen the ball joint nut but do not remove it completely yet. Leave the nut threaded on 2-3 turns to protect the ball joint stud threads and prevent the knuckle from dropping suddenly when separation occurs.
3. 3

   Separate ball joint from knuckle
   Position the ball joint separator tool between the upper control arm and the steering knuckle at the ball joint taper. Apply force according to the tool manufacturer's instructions to break the taper fit. Once separated, remove the ball joint nut completely and guide the knuckle down and away from the control arm ball joint stud.
   ⚠Do not strike the ball joint stud with a hammer as this can damage the threads. Use only a proper separator tool.
4. 4

   Support the knuckle assembly
   Use a bungee cord or wire to support the steering knuckle and prevent it from hanging on the brake hose or ABS sensor wiring. Ensure there is no tension on any flexible brake lines or electrical connections.
5. 5

   Remove control arm mounting bolts
   Locate the two control arm mounting bolts that secure the control arm to the chassis mounting bracket. Apply penetrating oil if needed. Using a 15mm socket and breaker bar, remove both front and rear control arm mounting bolts completely. Note the orientation and position of any washers or spacers for reassembly.
6. 6

   Remove upper control arm
   With all fasteners removed, maneuver the upper control arm out of the mounting bracket and away from the vehicle. You may need to rotate or angle the arm to clear the strut tower and chassis components. Inspect the mounting points on the chassis for damage or corrosion.
7. 7

   Prepare and install new control arm
   Clean the mounting surfaces on the chassis bracket with a wire brush. Compare the new upper control arm to the old unit to verify correct part. Position the new control arm into the chassis mounting bracket, aligning the bolt holes. Insert both control arm mounting bolts finger-tight but do not torque yet.
8. 8

   Connect ball joint to knuckle
   Remove the support holding the knuckle. Align the steering knuckle with the upper control arm ball joint stud. Push the knuckle up onto the ball joint stud, ensuring the taper is properly seated. Install the new ball joint castle nut and thread it down hand-tight.
9. 9

   Torque ball joint nut and install cotter pin
   Using a torque wrench and 18mm socket, torque the ball joint nut to specification. The nut must align with the cotter pin hole in the stud. If necessary, tighten the nut further (never loosen) until the next castle slot aligns with the hole. Install a new cotter pin through the castle nut and ball joint stud, then bend the ends of the cotter pin to secure it.
   Torque spec

   Ball Joint Nut88 Nm (65 lb-ft)
10. 10

    Reinstall wheel and lower vehicle
    Install the wheel and tire assembly onto the hub. Thread on all lug nuts by hand. Lower the vehicle until the tire just touches the ground but the full vehicle weight is not yet on the suspension. Tighten the lug nuts in a star pattern with a torque wrench to specification. Fully lower the vehicle so all weight is on the wheels.
    Torque spec

    Wheel Lug Nuts136 Nm (100 lb-ft)
11. 11

    Final torque of control arm bolts
    With the vehicle weight fully on the wheels (not on jack stands), use a torque wrench and 15mm socket to torque both control arm mounting bolts to specification. This step is critical to properly preload the control arm bushings. Torquing with the suspension unloaded will cause premature bushing failure.
    ⚠Vehicle must be at normal ride height with weight on wheels. Do not torque control arm bolts with suspension hanging.
    Torque spec

    Control Arm Bolts165 Nm (122 lb-ft)

Reassembly

1. Ensure all fasteners are torqued to specification in the correct sequence
2. Verify the new cotter pin is properly installed and bent to prevent backing out
3. Check that no brake lines, ABS wiring, or other components are pinched or stressed
4. Remove any tools or supports from under the vehicle

Verification

• Test drive the vehicle at low speed and verify no unusual noises from the front suspension
• Check for proper steering response and ensure the vehicle tracks straight
• After 50-100 miles, re-check the torque on the control arm bolts and ball joint nut
• Schedule a professional wheel alignment as suspension geometry has been disturbed

More procedures for this vehicle