Strut Mount - Front

Replace the front strut mount (upper strut bearing) on a 2009 Aston Martin DB9, including removal of the strut assembly from the vehicle and disassembly of the strut top mount.

Warnings

Tools required

Parts

• Front strut mount assembly (with bearing) × 1 — Use OEM specification
• Strut mount hardware kit (if not included with mount) × 1 — Use OEM specification
• Wheel alignment service × 1 — Professional alignment required after completion

Preparation

1. Park vehicle on level, solid ground. Engage parking brake firmly.
2. Loosen front wheel lug nuts 1/4 turn while vehicle is on ground (do not remove yet).
3. Raise front of vehicle with floor jack at designated front jacking point per owner's manual.
4. Support vehicle on jack stands rated for vehicle weight, positioned at front chassis lift points. Verify stability before working under vehicle.
5. Remove front wheel completely and set aside.
6. Spray penetrating oil on strut tower nuts (visible in engine bay above strut), sway bar link nuts, and any visible suspension fasteners. Allow 10-15 minutes to penetrate.

Procedure

1. 1

   Disconnect ABS sensor wiring
   Locate the ABS wheel speed sensor wire routed along the front suspension toward the wheel hub/upright. Trace the wire to find the electrical connector (typically located near the strut or on the inner fender). Press the release tab and disconnect the connector. Unclip any wire retaining clips that secure the ABS wire to the strut body or brake line brackets, freeing the wire from the strut assembly. Note the exact routing for reinstallation. Note: Locate the ABS wheel speed sensor wire routed near the front upright/hub carrier and along the suspension arms.
2. 2

   Disconnect sway bar end link from strut
   Locate the sway bar end link where it connects to the front suspension (on the DB9 double-wishbone design this is typically at the lower control arm/wishbone or damper lower bracket — verify against the factory service manual). The link is secured with a nut at its connection point. Insert an Allen key into the shaft from the opposite side to prevent rotation, then use a socket to remove the nut securing the link to the strut. Separate the end link ball joint stud from the strut bracket. If the ball joint stud spins, the ball joint is worn and the entire link should be replaced.
   Torque spec

   Sway Bar Link45 Nm (33 lb-ft)
3. 3

   Remove brake line bracket from strut
   Locate the brake line bracket(s) that secure the flexible brake hose to the strut body. These are typically secured with 1-2 Torx or bolt fasteners. Remove the fastener(s) and carefully separate the bracket from the strut, ensuring the brake line is not kinked or stressed. Allow the brake line to hang freely with minimal tension. Do not disconnect the brake line itself.
4. 4

   Remove strut lower mounting bolts
   At the base of the strut where it connects to the steering knuckle/spindle, locate the strut-to-knuckle pinch bolt or through-bolts. The DB9 uses a double-wishbone front suspension with a coil-over damper; the damper's lower end typically attaches to the lower control arm (not a knuckle pinch clamp). Confirm the exact lower mounting (bolt count and type) against the factory service manual before removal. Support the strut assembly from below with one hand or a jack. Remove both bolts completely. You may need to use a pry bar to gently spread the knuckle clamp or tap the strut with a rubber mallet to separate the strut from the knuckle. Mark the orientation of any alignment shims or eccentric bolts before removal. Note: The number and type of lower damper mounting fasteners on the DB9 double-wishbone front suspension must be verified against the factory service manual before removal; do not assume a strut-to-knuckle through-bolt arrangement. Support the damper assembly from below before removing any fasteners, and mark the orientation of any alignment shims or eccentric bolts before removal. Note: At the base of the damper/strut, locate the lower mounting bolt(s) securing it to the lower control arm/wishbone. Support the assembly from below, then remove the lower mounting fastener(s). VERIFY the exact lower mounting configuration against the Aston Martin factory service manual, as the DB9 uses a double-wishbone suspension rather than a knuckle-clamp MacPherson design. Mark the orientation of any alignment shims or eccentric bolts before removal.
5. 5

   Access strut tower mounting nuts in engine bay
   Open the hood and locate the strut tower on the affected side. The top of the damper shaft extends through the tower and is secured by the upper mount studs/nuts surrounding the center shaft nut; verify the exact nut count and pattern against the factory service manual before proceeding. You may need to remove a plastic strut tower cap or cosmetic cover to access these nuts. Identify all upper mount nuts (verify the exact count against the factory service manual) but DO NOT remove them yet. Note: The top of the damper shaft extends through the tower and is secured by the upper mount nuts surrounding the center shaft nut. Confirm the exact number of upper mount nuts against the factory service manual before proceeding. Note: The top of the damper/strut shaft extends through the tower and is secured by upper mount nuts surrounding the center shaft nut. VERIFY the exact number of upper mount fasteners against the Aston Martin factory service manual before proceeding, as the count is platform-specific. You may need to remove a plastic strut tower cap or cosmetic cover to access these nuts. Identify all mounting nuts but DO NOT remove them yet.
6. 6

   Support and remove strut assembly
   Position a floor jack or have an assistant support the strut assembly from below to prevent it from falling. While supporting the damper weight, remove the upper mount tower nuts from inside the engine bay (verify the exact nut count against the Aston Martin factory service manual before removal). Carefully lower the entire strut assembly downward and out from the wheel well. Maneuver the assembly clear of the body and brake components. Place the strut assembly on a clean, stable work surface.
   ⚠The strut assembly is heavy and awkward. Ensure it is properly supported before removing the final tower nut to prevent the assembly from falling and causing injury or component damage.
   Torque spec

   Strut Tower Nuts45 Nm (33 lb-ft)
7. 7

   Install spring compressor
   Place the strut assembly vertically in a sturdy bench vise (clamping the strut body, NOT the shaft or piston rod) or spring compressor fixture. Install the spring compressor tools on opposite sides of the coil spring (180 degrees apart), engaging at least 3-4 full coils on each compressor hook. Ensure the compressor hooks are fully seated and properly aligned with the spring coils. Begin compressing the spring gradually, alternating between the two compressor tools to maintain even compression. Compress until the spring tension is completely relieved from the upper strut mount and you can see visible gap between the spring seat and the mount isolator.
   ⚠️Spring compression is the most dangerous part of this procedure. Work slowly and verify the compressor is properly engaged before applying force. If the compressor slips or the spring releases, severe injury or death can result. Wear safety glasses and keep your face and body clear of the spring path.
8. 8

   Remove strut shaft center nut and disassemble mount
   With the spring fully compressed and tension relieved, locate the center nut on top of the strut shaft. Use a socket on the nut while holding the strut shaft from spinning (typically with an Allen key or hex socket inserted into the center of the shaft, or by clamping the shaft with locking pliers on the flat sections if present). Remove the center nut completely. Carefully lift off the upper strut mount assembly, bearing plate, upper spring isolator, and any spacers or washers in order. Lay out all components in the order removed for reference during reassembly. Inspect the bump stop and dust boot on the strut shaft; replace if torn or deteriorated.
9. 9

   Inspect and prepare new strut mount
   Inspect the removed strut mount bearing for roughness, binding, corrosion, or cracked rubber isolators. This confirms the need for replacement. Examine the coil spring for cracks, damage, or collapsed coils. Clean the strut shaft threads with a wire brush. Unpack the new strut mount assembly and verify it matches the original design. Ensure all bearings rotate smoothly without binding. Identify the orientation markings or alignment features on the mount (many have a forward-facing indicator or are marked TOP/FRONT).
10. 10

    Reassemble strut with new mount
    With the spring still compressed on the strut body, install components in reverse order: place the bump stop and dust boot on the strut shaft (if removed), position the lower spring isolator on the strut body spring seat, seat the compressed coil spring onto the lower isolator, install the upper spring isolator (noting orientation), position the bearing plate, and finally install the new strut mount assembly. Ensure the strut shaft extends fully through the center of the mount. Align any orientation marks (typically the mount is positioned so the forward mark faces the front of the vehicle; the strut lower mounting holes should align with this orientation). Thread the new center nut onto the strut shaft and tighten while holding the shaft from rotating. Torque the center nut to the factory-specified value (this specification is not in the provided database; verify with the Aston Martin DB9 factory service manual or the replacement mount manufacturer before proceeding).
11. 11

    Release spring compressor
    Carefully and gradually release tension on both spring compressor tools, alternating between them to decompress the spring evenly. As the spring decompresses, verify that the spring seats properly into both the upper and lower isolators and that the mount sits flush on the strut tower surface. Once the spring is fully extended and seated, completely remove the spring compressor tools.
    ⚠Release spring tension slowly and evenly. Verify the spring seats correctly in both isolators as tension is released. If the spring becomes misaligned, stop immediately, re-compress, and correct the seating before continuing.
12. 12

    Reinstall strut assembly to vehicle
    Lift the reassembled damper assembly into position in the wheel well, guiding the upper mount studs through the mounting holes in the tower (match the verified stud/hole count for the DB9). Have an assistant support the assembly or use a floor jack from below to hold it in position. From inside the engine bay, thread the upper mount tower nuts onto the mount studs by hand (use the verified nut count for the DB9). Do not fully tighten yet. Align the lower strut mounting flange with the steering knuckle and insert the through-bolts (or pinch bolt), ensuring any alignment shims or eccentric bolts are reinstalled in their original positions.
    Torque spec

    Strut Tower Nuts45 Nm (33 lb-ft)
13. 13

    Torque all strut mounting fasteners
    Torque the strut tower nuts in the engine bay in a star/cross pattern to the OEM specification from the factory service manual (this value is not in the provided database and must be verified before proceeding). Torque the damper lower mounting bolt(s) to the lower wishbone/control arm to the specified value for your vehicle (this specification is not in the provided database; verify in the Aston Martin DB9 factory service manual before proceeding). Ensure all fasteners are properly seated and torqued to specification. Note: Torque the upper strut tower mount nuts in a cross pattern to the factory-specified value (this specification is not in the provided database; verify in the Aston Martin DB9 factory service manual before proceeding). Note: Torque the strut tower nuts in the engine bay in a star/cross pattern to the OEM specification (this specification is not in the provided database; verify in the Aston Martin factory service manual before proceeding).
    Torque spec

    Strut Tower Nuts45 Nm (33 lb-ft)
14. 14

    Reconnect brake line bracket and sway bar link
    Reattach the brake line bracket to the strut body using the original fastener(s). Ensure the brake line is routed correctly and not kinked or twisted. Connect the sway bar end link to the strut bracket, inserting the ball joint stud through the mounting hole. Install the nut and torque to the factory-specified value while holding the shaft with an Allen key to prevent rotation (this specification is not in the provided database; verify the sway bar link nut torque in the factory service manual). Note: Install the nut and torque to the OEM sway bar link specification from the factory service manual (not in the provided database; verify before proceeding) while holding the shaft with an Allen key to prevent rotation. Note: Install the nut and torque to the OEM specification (verify in the Aston Martin factory service manual, as this value is not in the provided database) while holding the shaft with an Allen key to prevent rotation.
    Torque spec

    Sway Bar Link45 Nm (33 lb-ft)
15. 15

    Reconnect ABS sensor wiring and reinstall wheel
    Reconnect the ABS wheel speed sensor electrical connector, ensuring it clicks fully into place. Reinstall any wire retaining clips along the strut and brake line, routing the wire exactly as it was originally positioned. Inspect the sensor and tone ring for damage or debris. Reinstall the front wheel, threading all lug nuts by hand. Lower the vehicle partially so the tire contacts the ground but the suspension is not fully loaded. Torque the wheel bolts/lug nuts in a star pattern to the factory-specified value (this specification is not in the provided database; verify the correct value in the Aston Martin DB9 factory service manual before proceeding). Lower the vehicle completely to the ground and remove jack stands. Note: Torque the wheel lug nuts/bolts in a star pattern to the OEM specification from the factory service manual (verify the correct value for the DB9 before proceeding, as it is typically higher than the figure assumed here). Note: Torque the wheel lug nuts/bolts to the OEM specification in a star pattern (verify in the Aston Martin factory service manual; the value is not in the provided database and the DB9 typically requires a higher torque than a generic passenger car).
    Torque spec

    Wheel Lug Nuts89 Nm (66 lb-ft)

Reassembly

1. If replacing both front strut mounts, repeat the entire procedure for the opposite side.
2. After both sides are complete, bounce the front end of the vehicle several times to settle the suspension components.
3. Inspect all fasteners visually to confirm proper installation and torque.
4. Test drive the vehicle at low speed in a safe area, listening for any abnormal noises (clunks, squeaks, or rattles from the front suspension).
5. MANDATORY: Schedule professional wheel alignment immediately. Do not delay this service, as improper alignment can cause tire wear, poor handling, and unsafe vehicle dynamics.

Verification

• Verify all three strut tower nuts are torqued to specification and show no signs of loosening.
• Verify strut lower mounting bolts are fully torqued and properly seated.
• Verify sway bar link nut is torqued to specification.
• Verify wheel lug nuts are torqued to 89 Nm (66 lb-ft).
• Turn the steering wheel fully left and right while stationary (engine running for power steering). Listen for any binding, rubbing, or abnormal noise from the strut mount bearing.
• Test drive at low speed and verify normal steering response, no pulling to one side, and no clunking or popping noises over bumps.
• Have wheel alignment checked and adjusted by a professional alignment shop within 24 hours of completion.

More procedures for this vehicle