Definitive Lower Control Arm Fitment Guide for 1995 GMC G20 Van (G-Series, 4.3L V6 / 5.0L V8 / 5.7L V8 / 7.4L V8 / 6.5L Diesel)
The 1995 GMC G20 van uses a front lower control arm that crosses directly with Chevrolet G20 models and spans a wide range of 2WD G-Series vans. Production-vetted service replacements include the Moog RK620335 (left) and RK620336 (right) assemblies, the ACDelco Professional 45D2182 (left) and 45D2181 (right), and the GM OEM part numbers 15635803 (left) and 15635804 (right). All of these are bolt-on parts that include the ball joint and bushings.
Application
- GMC G20 (1992–1995) — 3/4-ton van, 2WD
- Chevrolet G20 (1992–1995) — identical chassis, shares all front suspension components
- Additional fitment — Moog and ACDelco numbers are backward-compatible to 1971 G10/G20/G30 vans when the same arm configuration (stamped steel, integrated bushing shells) is used. Verify bushing inner sleeve diameter when crossing to pre-1992 arms.
- Engine options — 4.3L V6 (LB4), 5.0L V8 (L03), 5.7L V8 (L31/L05), 7.4L V8 (L19), 6.5L Diesel V8 (L56/L65); the lower control arm is engine-agnostic.
Parts & Numbers
| Item | OEM Part No. | Moog | ACDelco Professional |
|---|---|---|---|
| Lower Control Arm, Left | 15635803 | RK620335 | 45D2182 |
| Lower Control Arm, Right | 15635804 | RK620336 | 45D2181 |
| Ball Joint (lower, separate service) | 88913405 | K6145 | 45D0068 |
| Control Arm Pivot Bolt & Nut Kit (M18) | — | BB778 (Moog bushing/bearing kit) | — |
Aftermarket arms such as Mevotech MS40520/MS40521 and TRW JTC1341/JTC1342 are also used by forum members; they match the same geometry and ball-joint taper as the Moog and ACDelco parts listed above.
Procedure
Always work on a level surface, use jack stands rated for the vehicle weight, and wear safety glasses. The front coil spring stores substantial energy.
- Loosen front wheel lug nuts, raise the front of the van, place jack stands under the frame rails, and remove the wheel.
- Remove the brake caliper and its bracket (18 mm sockets) and suspend the caliper with a hook; do not let it hang by the hose. Remove the rotor.
- Disconnect the sway bar end link from the lower control arm (typically a 15 mm bolt or a link with a 13 mm nut).
- Remove the lower shock absorber bolt (21 mm) and push the shock out of the bracket.
- Position a hydraulic jack under the center of the lower control arm coil spring seat, just enough to take the spring tension.
- Extract the cotter pin from the lower ball joint stud nut. Loosen the nut two full turns; do not remove it yet.
- Separate the ball joint from the steering knuckle with a pickle fork or a screw-type separator. Once the taper breaks free, remove the nut completely and lift the knuckle away.
- With the jack supporting the arm, remove the two large control arm pivot bolts (typically 21–24 mm) that secure the arm to the front crossmember.
- Slowly lower the hydraulic jack to relieve the coil spring tension. Remove the spring once the arm has dropped clear.
- Remove the old lower control arm, transfer any shims to the new arm in exactly the same position, and install in reverse order.
- Tighten all fasteners to specification (see torque table) and perform a fresh front-end alignment. For a broader replacement workflow, see the lower control arm replacement guide.
Torque Specifications
| Item | Value (ft-lbs) | Value (Nm) | Notes |
|---|---|---|---|
| Wheel Lug Nuts (8-lug) | 140 | 190 | Standard practice for GM 8-lug wheels; re-torque after 50 miles |
| Ball Joint Stud Nut | [VERIFY: exact spec against 1995 G20 factory manual; typical range for GM taper-stud joints is 60–75 ft-lbs] | [VERIFY: 81–102 Nm] | Lubricate threads lightly if dry |
| Lower Control Arm Pivot Bolts | [VERIFY: factory manual; typical range for M18 class-10.9 hardware on GM full-size trucks is 118–130 ft-lbs] | [VERIFY: 160–176 Nm] | Digressive torque-plus-angle procedure may apply on OE bolts |
| Lower Shock Bolt | [VERIFY: manual; typical range for 12mm hardware in this vehicle class is 50–65 ft-lbs] | [VERIFY: 68–88 Nm] | Use a new nylon-locking nut |
Notes & Common Mistakes
- Never attempt to remove the lower control arm without supporting the coil spring with a jack. A sudden release of spring tension can cause severe injury.
- Installing the arm upside-down will bind the ball joint and throw off alignment; the flat surface for the coil spring seat must face upward.
- Always replace the ball joint stud nut and cotter pin; reused fasteners can back off.
- The arm-to-crossmember bolts may require repeated heating and penetrating oil; seized bushings often force you to cut the bolt.
- Transfer the factory alignment shims exactly as they came out, or count the turns, to get close to the original caster/camber before driving to an alignment shop.
Diagnostic Reference
The 1995 GMC G20 is OBD-I (ALDL) and will not store related suspension DTCs. During a test drive, listen for:
- Clunking over bumps (worn ball joint or loose pivot bolts)
- Squeaking or popping on turns (dry or collapsed bushing)
- Vehicle pulling or steering wander (misalignment after arm replacement)
If you disturb the ABS wheel speed sensor (front left/right), later OBD-II vans (1996+) may set a C0040 or C0045 code; on the OBD-I G20 the system remains non-monitored.
FAQ
Q: Are GMC G20 and Chevrolet G20 lower control arms interchangeable? A: Yes. The chassis, part numbers, and geometry are identical across GMC and Chevy G20 vans built from 1992 through 1995. Pre-1992 arms may also fit, but check the bushing inner sleeve diameter. For the general difference between arm positions, see upper vs lower control arm.
Q: Do I need to replace the ball joint when I change the control arm? A: The Moog RK620335/RK620336 and ACDelco Professional arms come with a new ball joint pre-installed. If you reuse an old arm, install a fresh ball joint (Moog K6145 or ACDelco 45D0068) because the joint is already loaded.
Q: Will G30 (1-ton) lower control arms bolt onto my G20? A: Physically yes, but the G30 arm often uses a larger ball joint stud taper. Using a G30 arm on a G20 knuckle will require the matching ball joint or reaming the knuckle, which is not recommended for street use.
Q: My 1995 G20 has heavy front-end clunking after a pothole — is it the control arm bushing? A: It could be the lower control arm bushing or a failed ball joint. Have an assistant rock the steering wheel while you inspect the joint and bushings for movement. A torn bushing sleeve will produce a visible shift between the arm and the crossmember.