CV Boot - Inner

Replace the inner CV boot on a 2009 Aston Martin DB9 6.0L V12, requiring removal of the driveshaft from the differential to access and replace the inner boot assembly.

Warnings

Tools required

Parts

• Inner CV boot kit (includes boot, clamps, and grease) × 1 — Use OEM specification
• Differential output seal × 1 — Use OEM specification
• CV joint retaining circlip (if reusable clip is damaged) × 1 — Use OEM specification

Fluids

• 75W-140 synthetic gear oil — 0.5 qt

Preparation

1. Park the vehicle on a level surface and engage the parking brake.
2. Loosen the rear wheel lug nuts while the vehicle is on the ground.
3. Raise the rear of the vehicle and support it securely on jack stands placed at the manufacturer-recommended lift points.
4. Remove the rear wheel on the side requiring inner CV boot replacement.
5. Place a drain pan under the differential to catch any fluid that may escape when the driveshaft is removed.
6. Clean the area around the differential output flange and driveshaft connection with degreaser to prevent contamination during disassembly.

Procedure

1. 1

   Remove driveshaft from differential
   Locate the inner CV joint where it connects to the differential output flange. The connection uses bolts securing the CV joint flange to the differential. Remove the fasteners securing the inner CV joint to the differential output flange. The number of bolts should be verified against OEM documentation for this platform (do not assume a specific count without confirming against Aston Martin service data). Once all fasteners are removed, carefully pull the inner CV joint away from the transaxle output flange. Be prepared for possible fluid loss and have a drain pan ready, as some fluid may escape depending on the joint sealing design. Support the driveshaft to prevent it from dropping or placing stress on the outer CV joint. Note: The inner CV joint is typically secured to the output flange by multiple bolts in a circular pattern; verify the exact bolt count against Aston Martin service documentation before disassembly. Note: Once all fasteners are removed, carefully separate the inner CV joint from the differential output flange. If the joint uses a splined stub passing through an output seal, transaxle fluid may drain at this point — have a drain pan ready; if it is a sealed bolted flange, little or no fluid loss should occur. Note: Locate the inner CV joint where it connects to the rear transaxle output flange. The connection uses bolts securing the CV joint flange to the transaxle output. Remove the fasteners securing the inner CV joint to the output flange (verify exact bolt count against Aston Martin service documentation). Once all fasteners are removed, carefully pull the inner CV joint away from the output flange. Some gear oil may escape past the output seal, so position a drain pan. Support the half-shaft to prevent it from dropping or placing stress on the outer CV joint.
   Torque spec

   CV Bolts65 Nm (48 lb-ft)
2. 2

   Support and position driveshaft
   With the inner CV joint disconnected from the differential, carefully maneuver the driveshaft to provide working access. The outer CV joint remains connected to the hub assembly. Support the driveshaft using a bungee cord or wire tied to the suspension or chassis to prevent strain on the outer joint. Ensure the driveshaft is positioned to allow full access to the inner CV boot area without excessive articulation of either joint.
   ⚠Do not allow the driveshaft to hang unsupported by the outer CV joint alone, as this can damage the joint or boot.
3. 3

   Remove old inner CV boot clamps
   Inspect the inner CV boot and identify the clamp type (typically ear-type clamps or band clamps). Use the appropriate tool or side cutters to remove both the large and small boot clamps. Cut the clamps carefully to avoid damaging the CV joint housing or shaft. Once the clamps are removed, slide the old boot away from the joint toward the center of the shaft to expose the inner CV joint.
   ℹ️Mark the orientation of the tripod bearing or spider assembly relative to the shaft before disassembly if you plan to remove the joint components for inspection.
4. 4

   Clean and inspect inner CV joint
   Wipe away the old grease from the inner CV joint housing and tripod assembly using shop towels. Inspect the joint components for wear, scoring, pitting, or damage. Check the tripod bearings for smooth rotation and the housing for any cracks or excessive wear patterns. If the joint shows significant wear or damage, replacement of the entire driveshaft assembly may be necessary. Clean the shaft thoroughly where the new boot will seat, removing all old grease and debris. Use degreaser and a wire brush if necessary, then wipe clean and dry. Note: Verify the inner CV joint type against Aston Martin service documentation; it may be a tripod-style or a plunging ball-type (Rzeppa) joint. The internal components may be retained by a circlip on the shaft. Do not remove the joint internals unless replacement or detailed inspection is required. Note: The inner joint type on the DB9 must be verified against Aston Martin service documentation; it may be a tripod-style or a plunging ball-type (Rzeppa) joint. The internal components may be retained by a circlip on the shaft. Do not remove the joint internals unless replacement or detailed inspection is required.
   ℹ️Inner CV joints on the DB9 typically use a tripod-style joint. The tripod may be retained by a circlip on the shaft. Do not remove the tripod unless replacement or detailed inspection is required.
5. 5

   Install new inner CV boot
   Slide the small clamp onto the shaft first, followed by the new inner CV boot (small end first). Position the small end of the boot onto the shaft in the groove provided. Ensure the boot seats fully in the groove. Install the small clamp onto the boot and tighten it using the appropriate clamp tool. For ear-type clamps, crimp the ear until the clamp is secure. For band clamps, tighten and secure according to the clamp design. Verify the boot is not twisted and sits evenly in the groove.
   ℹ️Do not fully install the large end of the boot or add grease yet. This will be done after the joint is properly positioned.
6. 6

   Pack CV joint with grease
   Using the grease provided in the CV boot kit (or OEM-specified molybdenum disulfide CV grease), pack the inner CV joint housing thoroughly. Distribute grease evenly around the tripod bearings and housing interior. Use the full amount of grease provided in the kit, following the kit instructions or OEM specification for the correct fill quantity. Work the grease into all contact surfaces of the tripod and housing. Also apply grease to the shaft splines and the interior of the boot. Note: Use the full amount of grease provided in the kit, following the OEM-specified grease quantity for this joint. Note: Use the full amount of grease provided in the kit, following the kit instructions for the correct quantity for this joint.
   ℹ️Use only the grease type specified for CV joints. Do not substitute with generic bearing grease, as CV joints require specific lubrication properties.
7. 7

   Position and secure boot to joint housing
   Slide the large end of the boot over the CV joint housing. Ensure the boot seats properly in the groove on the housing. Before tightening the large clamp, verify the boot is not twisted and is positioned at the correct length. The boot should have a slight amount of slack (not stretched tight or excessively compressed) to allow for suspension articulation. Slide the large clamp into position over the boot on the housing. Tighten and secure the large clamp using the clamp tool. Verify both clamps are secure and the boot is properly seated at both ends.
   ⚠An over-stretched or over-compressed boot will fail prematurely. Ensure proper boot positioning before securing the large clamp.
8. 8

   Inspect differential output seal
   Before reinstalling the driveshaft, inspect the differential output seal for leaks, damage, or wear. If the seal shows any signs of deterioration or if differential fluid has been leaking, now is the time to replace it. Remove the old seal using a seal puller or flat screwdriver (carefully to avoid damaging the housing). Clean the seal bore thoroughly. Install the new seal using a seal driver or appropriate-sized socket, driving it in squarely until it seats fully. Apply a thin coat of the manufacturer-specified transaxle/final-drive oil to the seal lip before reinstallation of the half-shaft.
   ℹ️Replacing the output seal now can prevent future leaks and additional labor. The seal is inexpensive and accessible with the driveshaft removed.
9. 9

   Reinstall driveshaft to differential
   Carefully align the inner CV joint flange with the differential output flange. Ensure the splines engage properly if the joint uses a splined connection, or that the bolt holes align if using a bolted flange connection. Insert all fasteners by hand first to ensure proper alignment. Once all bolts are started, tighten them in a cross-pattern sequence to ensure even seating of the flanges. Torque the CV joint flange bolts in a cross-pattern to the Aston Martin specified value (verify exact torque against factory service documentation before assembly).
   ℹ️Ensure the inner CV joint is fully seated into the differential before tightening bolts. Incomplete engagement can cause vibration or driveline issues.
   Torque spec

   CV Bolts65 Nm (48 lb-ft)
10. 10

    Check differential fluid level
    After the driveshaft is reinstalled, check the differential fluid level. Locate the differential fill plug (typically on the side or rear of the differential housing). Remove the fill plug and check the fluid level. Check the fluid level according to the Aston Martin procedure for this transaxle (verify whether it uses a fill-to-level plug, a dipstick, or a specified fill volume). If fluid is low, add the Aston Martin-specified transaxle/differential lubricant (verify exact grade and specification in the service manual) until it reaches the proper level. Reinstall the fill plug and tighten it to specification if a torque value is provided in the service manual. Note: If fluid is low, add the OEM-specified transaxle/final-drive lubricant until it reaches the proper level as defined by the service manual. Note: If fluid is low, top up with the Aston Martin specified transaxle/final-drive oil (verify exact specification and viscosity against factory documentation) until it reaches the proper level.
    ⚠Operating the differential with low fluid can cause severe damage. Always verify fluid level after any work involving driveshaft removal.
11. 11

    Reinstall wheel and lower vehicle
    Reinstall the rear wheel onto the hub. Thread all lug nuts by hand to prevent cross-threading. Tighten the lug nuts in a star pattern using a torque wrench to the specified torque. Lower the vehicle carefully from the jack stands. Once the vehicle is on the ground, perform a final torque check on the lug nuts in a star pattern to ensure proper seating.
    Torque spec

    Wheel Lug Nuts89 Nm (66 lb-ft)

Reassembly

1. Reassembly follows the reverse order of disassembly, with particular attention to torque specifications for the CV joint bolts and wheel lug nuts.
2. Ensure all clamps on the new CV boot are secure and properly crimped before operating the vehicle.
3. Verify the differential fluid level is correct before test driving the vehicle.

Verification

• Start the vehicle and verify no unusual noises or vibrations from the rear driveline.
• Test drive the vehicle at low speeds, making turns in both directions to verify the CV joint operates smoothly without clicking, popping, or binding.
• After the test drive, inspect the new inner CV boot for any signs of grease leakage around the clamps.
• Check underneath the vehicle for any differential fluid leaks from the output seal area.
• Recheck the wheel lug nut torque after 50-100 miles of driving.

More procedures for this vehicle