Replacing the steering ball joint on a Mercedes C-Class

It is necessary to raise the front of the vehicle to replace the steering ball joint. Proceed with caution.

Locate the tools under the spare wheel in the trunk. Take the jack and the tire lever.

To loosen slightly the 5 wheel bolts.

Position the jack at the lifting notch and raise the vehicle.

Finish unscrewing the bolts, remove the wheel and position it under the vehicle to ensure safety in case of jack failure. Place the wheel bolts in a clean place.

Locate the ball joint retaining nut. It is located behind the brake disc, on the front side of the vehicle.

Using the 21 socket wrench, remove the nut.

Removing the steering knuckle is not always easy, especially if it is original and old. Use penetrating oil.

Refer to the ball joint extractor user manual. Place the extractor in place and begin tightening. If the force applied is sufficient, the ball joint should be driven out in one go.

If despite tightening the extractor the ball joint does not come out, add some penetrating oil and using a hammer, tap the top of the ball joint.

The kneecap after it is ejected.

In order not to change the alignment, the new ball joint must be reassembled in the same position as the old one.

Using the 21 mm flat wrench, loosen the lock nut.

Using a little paint or tape, mark the position of the ball joint on the threaded part.

Using the 13 flat wrench, hold the threaded rod (on the right in the photo) and using the 21 wrench, unscrew the ball joint (on the left in the photo). Count the number of turns.

Put a little threadlocker on the threaded part.

Screw in the new ball joint, counting the same number of turns as for removing the old one. If there is no mistake, the ball joint should arrive exactly at the place marked with the tape or paint.

Tighten the locknut using the 21 wrench.

Check that the ball joint housing is clean.

Put the new ball joint in place.

Hold the ball head with the 6mm Allen key and tighten the nut using the 21 key.

Depending on the brand of the new ball joint, the keys required for reassembly may be different from those for disassembly (e.g. Torx key instead of Allen key to hold the head). Make sure you have the right tools before changing the ball joint.

Insert a wheel bolt into its location and present the wheel against the brake disc. Using the tire lever, start tightening the first bolt.

Insert the following bolts, tightening them by hand. Move the wheel slightly to make sure it is seated correctly.

Lower the vehicle

Tighten the bolts in a star pattern.

Caution: When the wheels are removed, it is advisable to check the correct tightening of the bolts after the first uses.