Coil Springs - Front Pair

Replace the front coil springs on a 2007-2013 Mercedes-Benz S65 AMG, requiring disassembly of the front suspension strut assembly and use of a spring compressor.

Warnings

Tools required

Parts

• Front coil spring (left) × 1 — A2213240404 or equivalent OEM
• Front coil spring (right) × 1 — A2213240404 or equivalent OEM
• Strut mount bearing (if worn) × 2 — Use OEM specification
• Bump stop (if damaged) × 2 — Use OEM specification
• Strut bellows/boot (if torn) × 2 — Use OEM specification

Preparation

1. Park vehicle on level surface and engage parking brake
2. If equipped with ABC suspension, depressurize the system according to manufacturer procedure
3. Loosen front wheel lug nuts while vehicle is on ground (do not remove)
4. Raise front of vehicle with floor jack at approved lift points
5. Support vehicle securely on jack stands placed at frame reinforcement points behind front wheels
6. Remove both front wheels completely
7. Photograph or document suspension assembly orientation for reference during reassembly

Procedure

1. 1

   Disconnect sway bar end link
   Locate the sway bar end link connecting the sway bar to the strut. Insert the appropriate Allen key into the shaft to prevent rotation, then remove the upper nut connecting the link to the strut. Separate the end link from the strut mounting point. If link is seized, spray with penetrating oil and allow to soak.
   Torque spec

   Sway Bar Link Nuts55 Nm (41 lb-ft)
2. 2

   Disconnect ABS/wheel speed sensor
   Locate the ABS wheel speed sensor wire attached to clips on the strut body. Carefully unclip the wire from all mounting points on the strut and control arm to provide clearance for strut removal. Disconnect the electrical connector if necessary to prevent damage. Do not pull on the wire itself.
   ⚠ABS sensor wires are fragile. Damaged sensors will trigger ABS warning lights and require expensive replacement.
3. 3

   Separate ball joint from knuckle
   Locate the lower control arm ball joint connection to the steering knuckle. Remove the ball joint castle nut. Use a ball joint separator tool or pickle fork to separate the ball joint taper from the knuckle. Apply upward pressure on the control arm if needed. Once separated, support the lower control arm with a jack or jack stand to prevent it from dropping.
   ⚠Ball joint separator tools can damage boots. Inspect ball joint boot after separation and replace if torn.
   Torque spec

   Ball Joint Nut119 Nm (88 lb-ft)
4. 4

   Remove strut-to-knuckle pinch bolts
   Locate the two large bolts securing the bottom of the strut to the steering knuckle (pinch bolt arrangement). Support the knuckle and brake assembly with a bungee cord or wire to prevent stress on the brake hose. Remove both strut-to-knuckle bolts completely. You may need to rotate the knuckle or apply slight prying pressure to release the strut from the knuckle clamp.
   ⚠Support the knuckle/brake assembly before removing final bolt to prevent brake line damage.
   Torque spec

   Strut Bolts156 Nm (115 lb-ft)
5. 5

   Remove strut tower mounting nuts
   Open the hood and locate the three strut tower mounting nuts accessible from the engine compartment. They will be visible at the top of the strut tower. Remove all three nuts while having an assistant support the strut from below, or use a jack under the strut to support its weight. Carefully lower and remove the complete strut assembly from the vehicle.
   ⚠️Strut assembly is heavy (40+ lbs) and awkward. Ensure adequate support before removing final nut to prevent dropping.
   Torque spec

   Strut Tower Nuts50 Nm (37 lb-ft)
6. 6

   Install spring compressor
   Place the strut assembly in a strut vice or secure it firmly on a workbench. Install the spring compressor tool according to manufacturer instructions, ensuring the compressor hooks are evenly positioned on opposite sides of the spring and engaged securely in the coil valleys. Install compressor on at least 3-4 coils for stability. Begin compressing the spring gradually, alternating between compressor sides to maintain even compression.
   ⚠️Compress spring slowly and evenly. Check hook engagement frequently. An improperly installed compressor can slip and cause the spring to violently release.
   ⚠️Compress spring until there is visible gap between spring seat and spring, and spring can move freely. Do not over-compress.
7. 7

   Remove strut shaft nut
   With the spring fully compressed and loose, use a 22mm wrench on the strut shaft nut while holding the strut rod with an Allen key or special holding tool to prevent rotation. Remove the strut shaft nut completely. Carefully remove the upper strut mount, bearing plate, and spring seat, noting the orientation and order of all components.
   ⚠Ensure spring is adequately compressed before removing shaft nut. Spring should have visible free play.
8. 8

   Remove old spring and inspect components
   Carefully remove the compressed spring with the compressor still attached. Remove the lower spring insulator/seat if present. Inspect the strut mount bearing for roughness or wear, bump stop for tears or deterioration, and dust boot for damage. Replace any worn components. Inspect the strut shaft for leaks - if leaking, the strut should be replaced.
   ℹ️Keep spring compressor installed on old spring until ready to install on new spring for safety.
9. 9

   Install new spring
   If reusing spring compressor, carefully transfer it to the new spring, ensuring even compression as before. Verify the spring is correctly oriented - on some models, the spring end positioning is specific. Install lower spring seat/insulator onto strut body if applicable. Position the compressed new spring onto the strut, aligning the spring end with the seat locator tab. Install upper spring seat, bearing, and strut mount in the correct order and orientation as documented during disassembly.
   ⚠Spring orientation is critical. Top coil end must align with upper seat stop tab, and bottom coil with lower seat tab if present.
10. 10

    Install strut shaft nut
    Thread the strut shaft nut onto the strut rod by hand. Hold the strut shaft with Allen key or holding tool to prevent rotation. Torque the shaft nut to manufacturer specification (typically 50-60 Nm for this vehicle, though not specified in provided database - consult service manual for exact value). Ensure upper mount is properly seated before torquing.
    ℹ️Strut shaft nut torque not provided in database. Consult Mercedes-Benz service manual for exact specification before final tightening.
11. 11

    Release spring compressor
    Slowly and evenly release the spring compressor tension, alternating between sides. Monitor the spring as it seats into the upper and lower seats. Ensure the spring ends are properly located in their seat stops. Once fully released and spring is seated properly, carefully remove the spring compressor tool.
    ⚠️Release compressor slowly and evenly. If spring appears misaligned, stop and recompress to correct positioning.
12. 12

    Install strut assembly into vehicle
    With assistance or using a jack for support, lift the strut assembly into position. Guide the strut shaft through the strut tower opening first, then align the lower strut body with the steering knuckle. Install the three strut tower nuts finger-tight from the engine compartment. Insert the strut into the knuckle clamp and align bolt holes.
    Torque spec

    Strut Tower Nuts50 Nm (37 lb-ft)
13. 13

    Install strut-to-knuckle bolts and ball joint
    Install both strut-to-knuckle pinch bolts and tighten to specification. Ensure knuckle clamp is fully seated on strut body. Reconnect the lower control arm ball joint to the knuckle - align the taper and install the castle nut. Torque to specification. Install cotter pin if equipped, or ensure nut is properly secured per MB specification.
    Torque spec

    Strut Bolts156 Nm (115 lb-ft)

    Ball Joint Nut119 Nm (88 lb-ft)
14. 14

    Reconnect sway bar link and ABS sensor
    Reconnect the sway bar end link to the strut mounting point. Hold the shaft with Allen key and install the nut, torquing to specification. Reroute the ABS wheel speed sensor wire through all mounting clips on the strut and control arm. Reconnect electrical connector if disconnected. Ensure wire has adequate slack and will not be pinched or stretched during suspension travel.
    Torque spec

    Sway Bar Link Nuts55 Nm (41 lb-ft)
15. 15

    Final torque strut tower nuts
    From the engine compartment, torque all three strut tower nuts to specification in a star pattern. Repeat the entire procedure (steps 1-15) for the opposite side strut assembly to replace both front springs.
    Torque spec

    Strut Tower Nuts50 Nm (37 lb-ft)

Reassembly

1. Reinstall both front wheels and hand-tighten lug nuts in star pattern
2. Lower vehicle until wheels just contact ground but weight is still on jack stands
3. Torque wheel lug nuts to specification in star pattern
4. Remove jack stands and lower vehicle completely to ground
5. Rock vehicle side-to-side several times to settle suspension
6. Verify all fasteners are properly torqued and no tools or parts are left in engine compartment

Verification

• Start engine and verify no warning lights are illuminated on instrument cluster (ABC, ABS, etc.)
• Turn steering wheel full lock in both directions while stationary - listen for any binding or unusual noises
• Perform a careful test drive at low speed, checking for proper suspension operation, unusual noises, or vibrations
• Inspect for any fluid leaks around strut assemblies after test drive
• Schedule a professional four-wheel alignment immediately - suspension geometry has been disturbed and improper alignment will cause tire wear and handling issues
• After 50-100 miles, re-torque all suspension fasteners to specification and verify nothing has loosened

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