Changing a Defective Compression Ball Joint
Instructions for Replacing

If there is a knocking or clunking noise in the area of the front axle when the car is traveling over road bumps, potholes or curbs, then there is usually a defect in a component of the wheel suspension.

From dismounting the defective compression ball joint up to installing the new one: follow each step in the video.

Symptoms of faulty ball joint

The side of the front axle from which the (vibration) noise is emanating can already be determined during a test drive. The type of noise also already provides certain indications for maintenance regarding which components might be faulty.

Back in the workshop

On the vehicle lift, the trained eye of an expert may be sufficient to see where the noise is coming from, such as if the sealing sleeve of a ball joint is damaged. Nevertheless, at first glance it is not always obvious where the sound is coming from. In this case, all joints of the front axle need to be checked until the bad component is found. If the compression ball joint is defective as in our case, the control arm (wishbone) should also be examined more closely. If the control arm does not show any damage to the bearings, it is sufficient to change the bad compression ball joint. The exact work steps for replacing the broken compression ball joint vary from vehicle to vehicle and are specified by the vehicle manufacturer.

For an A-Class (W169) as in our case, you can replace the compression ball joint as follows:

Note: The pictures used in this practical tip and the procedure described for a replacement of the compression ball joint on a Mercedes Benz A160 (W169) are examples and may vary depending on the vehicle manufacturer and axle design.

1. Raise the vehicle and remove the front wheels.

2. To loosen the fastening screws and fixing nuts of the compression ball joint more easily, spray them with rust remover and allow to act for a few minutes.

3. Loosen the fastening screws of the broken ball joint on the control arm and remove the nuts.

4. Loosen and remove the fixing nut of the ball joint on the steering knuckle.

Tip: If the ball stud rotates, hold the ball stud in place with a hexagon socket.

5. Remove the bad or worn ball joint from the control arm.

6. Loosen the compression ball joint on the steering knuckle using a suitable special tool.

7. Clean the cone connection.

Tip: For better sealing and durability of the ball joint sleeve, a little silicone grease can be applied to the contact surface.

8. Insert new compression ball joint in the control arm and steering knuckle and tighten with new fixing nuts.

9. Reinstall front wheels. Lower the vehicle and tighten the wheel studs to the tightening torque specified by the vehicle manufacturer.

10. Measure the chassis and adjust it using the various holes on the compression ball joint if necessary.

11. Finally, carry out a test drive.

Assembly accessories in OEM quality: For easy installation of a LEMFÖRDER ball joint, all fasteners required for installation are supplied! This enables the workshop to carry out repairs quickly and safely.