Flexplate

Complete flexplate replacement on a 2009 Aston Martin DB9 6.0L V12, requiring transmission removal, torque converter separation, and crankshaft rear seal access.

Warnings

Tools required

Parts

• Flexplate (OEM replacement) × 1 — Use OEM specification
• Flexplate bolt set (new fasteners required) × 1 — Use OEM specification
• Torque converter bolts (if reusing, inspect for thread damage) × 1 — Use OEM specification
• Transmission pan gasket or RTV sealant × 1 — Use OEM specification
• Rear crankshaft seal (recommended replacement during access) × 1 — Use OEM specification
• Transmission fluid filter (if equipped) × 1 — Use OEM specification
• Exhaust gaskets and hardware (as needed for reassembly) × 1 — Use OEM specification

Fluids

• Touchtronic 6-speed ZF ATF — 9.5 qt

Preparation

1. Park vehicle on level surface and engage parking brake. Place wheel chocks at front wheels.
2. Disconnect battery negative terminal and secure cable away from terminal post. Wait 15 minutes for system discharge.
3. Raise vehicle on lift or position on four jack stands at manufacturer jacking points, ensuring adequate working height for transmission removal.
4. Remove engine cover panels and undertray panels to access transmission and exhaust components.
5. Place fluid drain pans beneath transmission pan and torque converter access area.
6. Label and photograph all electrical connectors, vacuum lines, and coolant hoses in engine bay for reference during reassembly.

Procedure

1. 1

   Drain transmission fluid and remove pan
   Locate transmission drain plug on pan (if equipped) and drain fluid into appropriate container. If no drain plug is present, carefully loosen pan bolts in cross-pattern starting from one corner, allowing fluid to drain gradually. Once drained, remove all pan mounting bolts and lower pan. Remove transmission filter if equipped. Inspect drained fluid for metal particles or debris indicating internal damage.
2. 2

   Remove exhaust system components
   Disconnect exhaust system from manifolds or catalytic converters. The DB9 V12 uses dual exhaust systems—remove exhaust clamps, hangers, and Torx fasteners securing exhaust to chassis mounting points. Lower exhaust system sufficiently to provide clearance for transmission removal. Support exhaust components with jack stands or wire to prevent damage.
3. 3

   Disconnect driveshaft from transmission
   Mark driveshaft flange orientation relative to transmission output flange for correct reinstallation phasing. Remove the driveshaft-to-transmission flange bolts (typically E-Torx fasteners). Support driveshaft center bearing if equipped, then carefully lower driveshaft and secure away from work area. Install transmission output shaft plug or cover opening with plastic bag to prevent fluid loss and contamination.
4. 4

   Disconnect transmission electrical connections and cooler lines
   Disconnect all electrical connectors from transmission including range selector sensor, speed sensors, solenoid pack harness, and any additional sensors. Use labeling system to mark each connector position. Disconnect transmission cooler lines at transmission using appropriate line wrenches to prevent damage. Cap or plug open lines immediately to prevent fluid loss and contamination. Remove any ground straps attached to transmission case.
5. 5

   Remove shift linkage and transmission crossmember
   Disconnect shift linkage or cable from transmission selector lever. Remove any mechanical or electronic linkage brackets attached to transmission. Support transmission with transmission jack positioned securely under pan with adapter or wood block to distribute load. Remove transmission crossmember mounting bolts (typically 4-6 Torx or E-Torx bolts to chassis). Carefully lower crossmember and remove from vehicle.
6. 6

   Install engine support and prepare for transmission removal
   Install engine support bar across engine bay or attach overhead support to engine lifting points. Apply slight upward tension to support engine weight once transmission is disconnected. Verify transmission jack is securely positioned and adjusted to proper height. Double-check that all electrical connectors, cooler lines, and mechanical linkages are disconnected.
7. 7

   Access torque converter bolts through starter opening
   Remove starter motor by disconnecting electrical connections and removing mounting bolts (typically E-Torx fasteners). Through the starter opening, access the torque converter-to-flexplate bolts. Rotate crankshaft using the appropriate socket on the crankshaft pulley/damper bolt (verify size against factory documentation) to bring each torque converter bolt into accessible position. The torque converter attaches to the flexplate with a specific number of bolts (verify exact count against Aston Martin service documentation for the ZF 6HP26). Remove all torque converter bolts and retain for inspection. Note: Rotate crankshaft using the correct socket size on the crankshaft pulley bolt (verify size against factory documentation) to bring each torque converter bolt into accessible position. Note: Rotate crankshaft using the appropriate socket on the crankshaft pulley/damper bolt (verify exact size against Aston Martin service documentation) to bring each torque converter bolt into accessible position. Note: Crankshaft turning socket (verify exact size against Aston Martin service documentation)
   ⚠Ensure torque converter remains fully seated in transmission pump during removal. Mark converter depth position if necessary to verify proper seating during installation.
8. 8

   Remove transmission-to-engine mounting bolts
   Locate all transmission bellhousing-to-engine block mounting bolts. The DB9 transmission bellhousing attaches to the engine block with a specific number of bolts of varying lengths around the perimeter (verify exact count and length positions against Aston Martin service documentation). Remove upper bolts first while supporting transmission with jack, then remove lower and side bolts. Note bolt lengths and positions for correct reinstallation. Check for any additional brackets or supports attached to bellhousing.
   Torque spec

   Transmission-to-Engine Bolts47 Nm (35 lb-ft)
9. 9

   Remove transmission assembly from vehicle
   Carefully slide transmission rearward away from engine, ensuring torque converter remains engaged with transmission pump. Move slowly and check for any remaining connections or interference. Once bellhousing clears alignment dowels, lower transmission on jack and maneuver from under vehicle. Place transmission on secure work surface. Immediately install torque converter holding strap or bolt to prevent converter from sliding out during handling.
10. 10

    Inspect and remove damaged flexplate
    With transmission removed, inspect flexplate for cracks, heat discoloration, damaged ring gear teeth, or elongated bolt holes. Install flywheel holding tool or have assistant use large pry bar against ring gear to prevent crankshaft rotation. Remove all flexplate mounting bolts in cross-pattern. The V12 engine secures the flexplate to the crankshaft flange with a specific number of bolts (verify exact count against Aston Martin service documentation). Remove flexplate from crankshaft and inspect crankshaft flange for damage or debris.
11. 11

    Inspect crankshaft flange and rear seal
    Clean crankshaft flange thoroughly with brake cleaner and lint-free cloth. Inspect flange surface for cracks, scoring, or damage. Check crankshaft endplay using dial indicator and compare against the factory-specified endplay range for this engine (verify value against factory documentation). Inspect rear crankshaft seal for leakage. If seal shows any oil seepage, now is optimal time for replacement as access is fully open. Check alignment dowel pins in crankshaft flange are present and undamaged. Note: Check crankshaft endplay using dial indicator and compare against factory specification (verify value against factory documentation). Note: Check crankshaft endplay using a dial indicator against the Aston Martin specification for the 6.0L V12 (verify exact range from service documentation).
12. 12

    Install new flexplate to crankshaft
    Verify new flexplate matches original part number and ring gear tooth count. Position new flexplate onto crankshaft flange, aligning bolt holes and ensuring proper orientation (note any offset or asymmetric bolt patterns). Install new flexplate bolts finger-tight in all positions. If the manufacturer specifies threadlocker, apply the specified grade to bolt threads (note: factory torque-to-yield bolts are often pre-coated and may require no additional threadlocker). Using flywheel holding tool to prevent rotation, torque flexplate bolts to the factory-specified torque in the exact factory-specified sequence (confirm whether a cross-pattern or specific pattern applies, and confirm the torque and any angle-tightening pass, against Aston Martin service documentation). Perform final tightening using the factory-specified torque and angle sequence for these torque-to-yield fasteners. Note: Apply threadlocker only if specified by the manufacturer for these fasteners. Using flywheel holding tool to prevent rotation, torque flexplate bolts in the factory-specified sequence (verify pattern and torque/angle spec against factory documentation). Note: Do not add threadlocker unless specified by Aston Martin; these torque-to-yield bolts may come with factory pre-applied adhesive—verify against OEM specification before installation. Note: Complete the torque-to-yield procedure (initial torque followed by specified angle, if applicable) per Aston Martin specification rather than a simple second pass.
    ⚠Use only new flexplate bolts. These are torque-to-yield fasteners that permanently deform during installation. Reuse will result in insufficient clamping force and potential bolt failure.
    Torque spec

    Flexplate Bolts85 Nm (63 lb-ft)
13. 13

    Prepare transmission for installation
    Verify torque converter is fully seated in transmission pump by measuring depth from bellhousing face to torque converter pilot and comparing against the factory-specified seating dimension for the ZF 6HP26 (do not rely on any assumed value—confirm the exact seating depth against Aston Martin/ZF service documentation). Verify torque converter rotates freely. Clean bellhousing mating surface and engine block mounting face. Inspect transmission alignment dowels in engine block for damage. Apply small amount of high-temperature grease to torque converter pilot nose. Note: Verify torque converter is fully seated in transmission pump by measuring depth from bellhousing face to torque converter pilot and compare against the factory-specified seating depth (verify value against factory documentation). Note: Verify torque converter is fully seated in transmission pump by measuring depth from bellhousing face to torque converter pilot per the ZF/Aston Martin specification (confirm exact value from service documentation—do not rely on an assumed figure).
14. 14

    Install transmission assembly to engine
    Position transmission on transmission jack and raise into position beneath vehicle. Carefully align transmission with engine, ensuring torque converter pilot aligns with crankshaft center. Slide transmission forward onto alignment dowels, rotating torque converter slightly if needed to engage pilot. Do not force—transmission should slide forward smoothly once properly aligned. Install transmission-to-engine mounting bolts and tighten in cross-pattern to specification.
    ⚠Never use transmission mounting bolts to pull transmission to engine. If transmission does not mate fully, remove and check for obstructions or misalignment.
    Torque spec

    Transmission-to-Engine Bolts47 Nm (35 lb-ft)
15. 15

    Install torque converter to flexplate bolts
    Rotate crankshaft to align torque converter bolt holes with flexplate holes. Install torque converter-to-flexplate bolts through starter motor opening. Apply threadlocker only if specified by the manufacturer. Rotate crankshaft to access each bolt position, tightening each bolt to specification in sequence. Verify all bolts are installed and torqued properly.
    Torque spec

    Torque Converter Bolts45 Nm (33 lb-ft)
16. 16

    Reinstall starter motor and crossmember
    Reinstall starter motor to bellhousing or engine block, reconnecting electrical connections. Install transmission crossmember and tighten mounting bolts to chassis. Remove transmission jack once crossmember is secured. Remove engine support bar or overhead support.
17. 17

    Reconnect driveshaft, shift linkage, and cooler lines
    Reinstall driveshaft to transmission output flange, aligning marks made during removal to maintain driveline phasing. Torque driveshaft flange bolts to specification. Reconnect shift linkage or cable to transmission selector. Reconnect transmission cooler lines using new sealing washers if equipped. Reconnect all electrical connectors to transmission sensors and solenoid pack using labels as reference. Reinstall all ground straps.
18. 18

    Reinstall exhaust system components
    Raise exhaust system into position and install all mounting brackets, hangers, and clamps. Use new exhaust gaskets at manifold or catalytic converter connections. Tighten all exhaust fasteners to specification. Verify adequate clearance exists between exhaust components and chassis, driveshaft, and suspension components.
19. 19

    Reinstall transmission pan and refill fluid
    Install new transmission filter if equipped. Clean transmission pan and mounting surface thoroughly. Install new pan gasket or apply appropriate RTV sealant per manufacturer specification. Install pan and tighten bolts in cross-pattern to specification. Fill transmission with the correct ZF-specified ATF through the fill plug (this transmission uses a fill-plug/level-check procedure, not a conventional dipstick). Perform the fluid level check at the manufacturer-specified fluid temperature. A pan-only partial drain-and-refill releases only a portion of the total fluid (full dry fill is larger); verify exact partial and total capacity and fill level against factory documentation. Do not overfill. Note: Fill transmission with correct ZF ATF fluid through the fill plug. Fill quantity depends on whether only the pan was dropped (partial fill) or the unit was fully drained; verify exact fill procedure and capacity against factory documentation and set level via the overflow/fill-plug method at specified fluid temperature. Do not overfill. Note: Fill transmission with correct ZF Lifeguard ATF through the fill/level plug (this transmission is typically sealed with no dipstick). Set level with fluid at the specified temperature per Aston Martin/ZF procedure; verify refill capacity against service documentation. Do not overfill.
20. 20

    Reinstall undertray panels and reconnect battery
    Reinstall all undertray panels and engine covers removed during disassembly. Reconnect battery negative terminal. Lower vehicle from lift or jack stands.

Reassembly

1. Torque all fasteners to specified values using cross-pattern sequences where applicable.
2. Ensure all electrical connectors are fully seated with locking tabs engaged.
3. Verify driveshaft phasing marks are properly aligned before final torque.
4. Double-check transmission cooler line connections for proper seating and no cross-threading.
5. Install new flexplate bolts—never reuse original fasteners.

Verification

• Start engine and verify no abnormal noises from flexplate or torque converter area. Listen for clicking, grinding, or rattling that would indicate loose or damaged components.
• With engine running and parking brake engaged, cycle transmission through all gear ranges and verify smooth engagement without harsh shifts or slippage.
• Check transmission fluid level with engine at operating temperature and in Park position on level surface. Add fluid as needed to bring to proper level on dipstick.
• Inspect for fluid leaks at transmission pan, cooler lines, and all connection points after 15-minute test run.
• Perform test drive including acceleration, deceleration, and all gear ranges. Verify no vibration, abnormal noise, or driveline issues.
• After test drive, re-inspect all fasteners and connections. Re-torque flexplate and torque converter bolts if manufacturer specifies re-torque procedure.
• Monitor transmission fluid condition and level over first 100 miles of operation.

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