Control Arms – General Information, Rebuilding, and Aftermarket Replacements

Overview

This guide covers the maintenance, rebuilding, and replacement options for the alloy control arms on the Porsche 944 (16v engine). The control arms are critical for front suspension stability, but their nylon cup and ball joint assembly can wear prematurely, especially in high-performance driving or lowered vehicles. This guide provides steps to rebuild the control arms using aftermarket kits or replace them with aftermarket options, ensuring safe and reliable suspension performance.

Pink and blue text represent links to additional resources, tools, parts, and partner websites.

Tools Required

• 19mm (3/4 inch) socket and ratchet
• 30mm (1-3/16 inch) socket or seal driver
• Vise
• Small flathead screwdriver
• Torque wrench (capable of 25 Nm / 18 ft-lbs and 100 Nm / 74 ft-lbs)
• Wire brush or sandpaper (for removing epoxy)
• CV joint grease
• Epoxy adhesive

Parts Required

• Control arm rebuild kit (e.g., KLA Industries nylon bushing kit or SSI Auto bronze bushing kit with chrome-moly ball joints, 944 341 027 07)
• Ball joint boot (from early 944 ball joint, 171 407 365 G)
• Optional: Aftermarket control arm (e.g., Charlie Arms for 1987–1991, 944 341 027 07)

Required Additional Procedures

Steps in these procedures are required to complete this process:

• Control Arm Replacement

Step-by-Step Procedure

Step 1: Remove the Control Arm

1. Follow this link to ensure this step – Control Arm Replacement – of the process is followed accurately.

Note:
Ensure the vehicle is securely lifted and supported on jack stands before starting.

Step 2: Prepare the Control Arm

2. Use a wire brush or sandpaper to remove any epoxy material from the control arm to expose the bottom of the ball joint, specifically the circlip.
3. Carefully remove the rubber grease boot from the control arm, retaining the boot’s spring for reuse.

Step 3: Disassemble the Ball Joint

4. Place a 30mm (1-3/16 inch) socket over the pin side of the ball joint and a smaller nut or socket against the bottom cover of the ball joint.
5. Squeeze the assembly in a vise just enough to access the circlip.
6. Use a small flathead screwdriver to pry the circlip out of its groove in the control arm.
7. Remove the assembly from the vise and disassemble the ball joint components (bushing, ball, spacers, and cover plate).

For kits reusing the ball joint:
Inspect the ball joint pin for cracks or unusual wear. Replace with a new ball joint (944 341 027 07) if damaged.

Step 4: Install New Bushing and Reassemble

8. Place the top ball joint bushing into the control arm’s opening, ensuring even alignment.
9. Using a vise, press the bushing into the control arm with a 30mm (1-3/16 inch) socket or seal driver. Place a piece of wood between the control arm and vise to prevent damage.
10. Apply CV joint grease to the bushing cup and the ball joint.
11. Insert the ball into the cup, followed by the lower cup, spacer ring, spring, another spacer, and cover plate.
12. Squeeze the assembly in the vise and install the circlip securely.
13. Apply epoxy to the bottom of the ball joint opening to secure the circlip.

Step 5: Reinstall the Control Arm

14. Follow this link to ensure this step – Control Arm Replacement – of the process is followed accurately.

Note:
Torque control arm mounting bolts to 100 Nm (74 ft-lbs).

Step 6: Optional Aftermarket Control Arm Installation

15. If installing aftermarket control arms (e.g., Charlie Arms, 944 341 027 07), follow the manufacturer’s instructions for your specific kit.

For Porsche 944 (1989–1991):
Ensure the control arms are designed for late-model 944s (1987–1991). Verify compatibility with your sway bar type (OE or aftermarket).
Torque mounting bolts to 100 Nm (74 ft-lbs) and check for proper alignment.

Post Procedure Checklist

• Verify the control arm is securely mounted with no play.
• Check the ball joint boot (171 407 365 G) for tears and ensure it’s properly seated.
• Perform a test drive of 5 miles (8 km) to check for unusual noises or vibrations.
• Inspect the front suspension alignment and adjust if necessary.

Sources

• Clark’s Garage
• Pelican Parts
• Porsche 944 Workshop Manuals
• Youtube