Mercedes-Benz S-Class Front Airbag Strut Replacement W221 W216

A problem many Mercedes-Benz S-Class and CL-Class is the air strut failing, which causes the vehicle to drop at the corner where the strut fails. To fix this problem, you will need to replace the failed air strut.

Symptoms

• Front suspension strut failed
• Front Left or right corner lowers itself when parked
• One side lower than the other
• Car sagging or lower in one corner

What you will need

• Air Suspension Bag / Strut
  • 4MATIC MODELS -Front Air Struts for S-Class / CL-Class
    • W221 Left Air Strut 4Matic
      • (Applies to W216 also
      • Related Part Number: 2213200438, 2213205313, 2213201738
    • W221 Right Air Strut 4Matic
      • Applies to W216 CL models as well.
      • Related Part Number: 2213200538 2213200338 2213203213 2213205413
  • RWD MODELS - Front Air Struts for S-Class / CL-Class without 4Matic
    • W221 Front Left Air Strut without 4Matic
    • W221 Front Right Air Strut without 4Matic
• Vehicle Jack
• Jack Stands
• Mechanic Toolset Metric 
• Front End Service Kit
  • It will be needed for pressing ball joints.
  • Do not use the FORK type. The ball joint protective boots may get damaged.

Procedure

Below you will find instructions on how to replace front airmatic suspension from 2007 to 2013 Mercedes-Benz S Class vehicles.

1. Park, your Mercedes-Benz, set the parking brakes, shifter in park, and remove the key from the ignition. Before you jack up the car, loosen the lug nuts.
2. Jack up the car and secure it with jack stands.
3. Remove the airline to the top of the air strut. Use a 12mm open-end wrench to loosen the nut. Loosen the nut slowly and allow it to leak the air before you fully disconnect the line. Once the nut is unscrewed, you remove the airline by pulling it out.
4. Remove three 13 mm nuts that connect the strut to the strut tower. We recommend that the last nut you loosen up, you don't remove it completely until you are ready to remove the air strut and replace it.
5. Disconnect the upper control arm. Remove the 17mm bolt. Next, use a ball joint puller to separate the two.
6. Disconnect the electrical plug for your S-Class air suspension strut and ABS line. Pull up the small C clip, then pull out the connector.
7. Remove the nut (4matic) or the set screw (not-4matic / RWD only).
8. Now you are ready to replace the airmatic strut on the Mercedes S-Class. Install the new S-Class air strut in reverse order.
9. Torque the bolts on top of the strut, upper control arm, and lower control arm.
10. Lower the vehicle slowly. Dropping the car to the ground too quickly risks damage to the airmatic strut.

Mercedes S Class Air Strut

Note that the front air struts are different for the rear-wheel-drive models versus the 4Matic models. The air strut on 4Matic models has a ball joint at the bottom where it connects to the lower control arm.

While the non-4matic (rear-wheel-drive models), the strut has a hole at the bottom, and a set screw is used.