Front Struts - Pair

Remove and replace both front strut assemblies on a 2007-2013 Mercedes-Benz S65 AMG, including disconnection of suspension components and airmatic system depressurization.

Warnings

Tools required

Parts

• Front strut assembly (left) × 1 — A2213208613 or equivalent OEM/Bilstein
• Front strut assembly (right) × 1 — A2213208713 or equivalent OEM/Bilstein
• Strut tower mounting nuts × 6 — Self-locking M10 nuts
• Ball joint nut × 2 — Use OEM specification
• Sway bar link nuts (if damaged) × 2 — Use OEM specification

Preparation

1. Verify replacement struts are correct for S65 AMG application (different from standard S-Class)
2. Connect Mercedes-Benz Star Diagnostic tool to vehicle
3. Use diagnostic tool to enter 'Suspension Service Mode' and depressurize Airmatic system completely
4. Allow minimum 10 minutes for system depressurization to complete
5. Loosen wheel lug nuts while vehicle is on ground
6. Raise vehicle on lift or use jack stands at manufacturer-specified jacking points
7. Remove both front wheels completely
8. Spray all suspension fasteners with penetrating oil and allow to soak 15-20 minutes

Procedure

1. 1

   Access strut tower mounting area
   Open hood and locate strut tower on the side being serviced. Remove plastic strut tower cover by releasing retaining clips. You will see three mounting nuts securing the top of the strut assembly. Do NOT remove these nuts yet.
2. 2

   Disconnect brake wear sensor and ABS wiring
   Locate brake pad wear sensor connector and ABS wheel speed sensor connector on the strut/steering knuckle area. Disconnect both connectors and carefully unclip wiring from any retaining clips on the strut body. Route wiring clear of work area.
3. 3

   Remove sway bar end link
   Locate sway bar end link connection at the strut. Use an Allen key to hold the shaft while removing the top nut with a 16mm wrench. Disconnect end link from strut and allow it to hang from sway bar. Inspect link for wear and replace if rubber bushings are cracked or torn.
   Torque spec

   Sway Bar Link82 Nm (61 lb-ft)
4. 4

   Disconnect ball joint from steering knuckle
   Locate the upper or lower control arm ball joint connection to the steering knuckle (configuration varies by production year). Remove the ball joint castle nut completely using a 21mm socket. Use a ball joint separator tool to break the taper connection. Do not hammer directly on threads. Once separated, support the control arm to prevent stress on bushings.
   ⚠Ball joint taper connections require proper separation tools. Using hammers or excessive force can damage steering knuckle or control arm.
   Torque spec

   Ball Joint Nut119 Nm (88 lb-ft)
5. 5

   Remove strut-to-knuckle mounting bolts
   Locate the two large bolts connecting the bottom of the strut to the steering knuckle (pinch bolts). These are typically 18mm or 19mm head bolts. Support the steering knuckle with a jack or stand. Remove both bolts completely. You may need to spread the knuckle slightly with a pry bar to release the strut.
   ⚠The steering knuckle and brake assembly are heavy. Ensure adequate support before removing strut bolts to prevent components from falling.
   Torque spec

   Strut Bolts156 Nm (115 lb-ft)
6. 6

   Disconnect Airmatic air line and level sensor
   Locate the air supply line connected to the strut (usually has a quick-disconnect fitting). Press the release collar and carefully disconnect the air line. Locate the suspension level sensor link arm connected to the control arm or knuckle and disconnect it by removing the retaining clip or small bolt. Mark orientation for reinstallation.
   ⚠Even after depressurization, residual air pressure may remain. Keep face and body clear when disconnecting air lines.
7. 7

   Remove strut tower mounting nuts
   From the engine bay, have an assistant support the strut assembly from below. Remove the three nuts securing the strut to the strut tower using an 18mm socket. Once all nuts are removed, carefully lower the strut assembly down and out through the wheel well. The assembly is heavy (approximately 30-40 lbs).
   ⚠Strut assemblies are heavy and awkward. Use proper lifting technique and have an assistant support the assembly during removal.
   Torque spec

   Strut Tower Nuts50 Nm (37 lb-ft)
8. 8

   Install new strut into strut tower
   Position the new strut assembly from below, guiding it up through the wheel well and into the strut tower. Align the three mounting studs with the holes in the strut tower. Install NEW self-locking nuts onto the studs and hand-tighten. Torque the three strut tower nuts in a star pattern to specification.
   Torque spec

   Strut Tower Nuts50 Nm (37 lb-ft)
9. 9

   Connect strut to steering knuckle
   Lift the steering knuckle and align it with the strut mounting flange. Insert both strut-to-knuckle bolts and ensure they are fully seated through both the knuckle and strut bracket. Install nuts and torque to specification. Verify the knuckle is properly seated in the strut fork with no gaps.
   Torque spec

   Strut Bolts156 Nm (115 lb-ft)
10. 10

    Reconnect ball joint and sway bar link
    Align the control arm ball joint with the steering knuckle taper. Insert the ball joint stud and install a NEW castle nut. Torque to specification and install cotter pin if equipped. Reconnect the sway bar end link to the strut, hold the shaft with an Allen key, and torque the nut to specification.
    Torque spec

    Ball Joint Nut119 Nm (88 lb-ft)

    Sway Bar Link82 Nm (61 lb-ft)
11. 11

    Reconnect Airmatic air line and level sensor
    Push the air line connector firmly into the strut fitting until it clicks and locks. Tug gently to verify connection. Reconnect the suspension level sensor link arm to the control arm or knuckle in the orientation marked during disassembly. Secure with retaining clip or bolt.
12. 12

    Reconnect electrical connections
    Reconnect the ABS wheel speed sensor connector and brake pad wear sensor connector. Secure all wiring in original routing clips on the strut body. Ensure no wires are pinched, stretched, or in contact with moving suspension components.
13. 13

    Repeat for opposite side
    Perform steps 1-12 on the opposite front strut assembly. Ensure all torque specifications are followed identically on both sides.
14. 14

    Reinstall wheels and initialize suspension system
    Install both front wheels and torque lug nuts to specification in a star pattern. Lower vehicle to ground. Using the Mercedes-Benz Star Diagnostic tool, exit Suspension Service Mode and run the 'Airmatic System Initialization' procedure. This will repressurize the system and calibrate level sensors. Monitor for any fault codes or air leaks.
    ⚠Do not drive vehicle until Airmatic system initialization is complete and diagnostic tool confirms no faults. Driving with uninitiated system can cause damage.
    Torque spec

    Wheel Lug Nuts183 Nm (135 lb-ft)

Reassembly

1. Reinstall strut tower plastic covers in engine bay
2. Verify all electrical connectors are fully seated and secured
3. Check that no tools or parts were left in wheel wells or engine bay
4. Verify all fasteners have been torqued to specification using your torque wrench

Verification

• Using Star Diagnostic tool, verify no suspension system fault codes are present
• Perform visual inspection for any air leaks around strut air line connections
• Start vehicle and allow Airmatic system to cycle through normal leveling process
• Verify vehicle sits at correct ride height on level ground (should self-level within 30 seconds)
• Perform slow-speed test drive in safe area, checking for unusual noises, vibrations, or handling issues
• CRITICAL: Have four-wheel alignment performed by qualified technician with Mercedes-Benz specifications immediately after test drive
• After alignment, verify steering wheel is centered and vehicle tracks straight
• Re-check all torque specifications after 50-100 miles of driving

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