Control Arm Replacement

Introduction

From the 1985.5 model year onward, 944s use aluminum control arms with non-replaceable ball joints; early cars use steel control arms with replaceable ball joints.

Signs that a control arm or ball joint needs replacement:

• Torn or cracked ball joint boot (raises suspicion but not conclusive on its own)
• Knocking sounds from the front suspension
• Noticeable play when pushing up on the control arm near the ball joint

If the boot is torn but the ball joint itself is sound, a temporary repair is possible by installing the boot from an early 944 ball joint. The early ball joint (Porsche part no. 171 407 365 G) is significantly less expensive than a complete new aluminum control arm.

Control arms are available rebuilt from several sources as well as new from Porsche. Rebuilt arms typically carry a two- to three-year warranty.

Tools

• Metric socket set
• Metric wrench set
• Torque wrench
• Rubber hammer

Removal

1. Place the vehicle on jack stands.
2. Remove the front wheels.
3. Remove the skid pans.
4. Disconnect the front sway bar from the body and the control arm and remove the sway bar from the car.
5. Mark the orientation of the eccentric bolt to the control arm (the eccentric bolt attaches the rear of the control arm to the body). Use brightly colored nail polish or a paint marker.
6. Remove the nut and bolt that attaches the spindle to the ball joint.
7. If the rear eccentric bolt bushing is to be replaced, remove the lock nut at the rear that attaches the eccentric to the bushing.
8. Remove the lock nut at the front of the eccentric bolt.
9. Remove the two bolts that attach the eccentric bolt bushing to the body.
10. Remove the bolt and nut that attaches the front of the control arm to the cross-member.
11. Using the rubber hammer, tap on the top of the control arm to free the ball joint from the spindle and remove the control arm.

Installation

1. If the eccentric bolt assembly was removed: a. Transfer the eccentric bolt orientation mark from the old control arm to the new one. b. Attach the eccentric bolt to the control arm aligned with the transferred mark. c. Torque the eccentric bolt lock nut to 100 Nm (74 ft-lb).

   Note: All lock nuts should be replaced with new hardware.

2. Position the control arm in the car and install the control arm-to-cross-member bolt.

3. Slide the eccentric bushing onto the eccentric bolt. Bolt the bushing to the body with two bolts and loosely install the rear eccentric lock nut.

4. Fit the ball joint shaft into the spindle assembly, ensuring it is fully inserted.

5. Install the ball joint-to-spindle bolt and lock nut. Torque to 50 Nm (37 ft-lb).

6. Place a jack under the ball joint with a block of wood on the jack pad. Raise the jack until it just supports the weight of the car.

7. Torque control arm bolts:

Fastener	Torque
Control arm to cross-member	65 Nm (48 ft-lb)
Control arm eccentric bolt assembly to body	46 Nm (34 ft-lb)

8. Remove the jack and attach the front sway bar to both the body and the control arm.

Sway bar fastener	Torque
Sway bar to body (M8)	23 Nm (17 ft-lb)
Sway bar to control arm — aluminum control arms	25 Nm (18 ft-lb)
Sway bar to control arm — steel control arms	23 Nm (17 ft-lb)

9. Install the front wheels.