Transmission R&R - Automatic

Complete removal and reinstallation of the 6-speed ZF automatic transmission (Touchtronic) from a 2009 Aston Martin DB9, including driveline disconnection, transmission crossmember removal, and torque converter separation.

Warnings

Tools required

Parts

• Transmission fluid pan gasket × 1 — Use OEM specification
• Transmission drain plug crush washer × 1 — Use OEM specification
• Driveshaft center bearing bolts (if reused bolts show thread distortion) × 1 — Use OEM specification
• Transmission mount through-bolt and hardware × 1 — Use OEM specification
• Rear differential drain plug washer × 1 — Use OEM specification
• Flywheel bolts (TTY, replace during reinstallation) × 8 — Use OEM specification

Fluids

• transmission_auto — 9.5 qt

Preparation

1. Park vehicle on level ground and engage parking brake. Ensure adequate overhead clearance for lift operation.
2. Disconnect negative battery terminal and isolate cable away from battery post. Wait 10 minutes for airbag system capacitor discharge.
3. Raise vehicle on lift to comfortable working height (chest-high transmission pan access). Ensure lift engagement points are secure on chassis jacking points.
4. Remove rear wheels and set aside.
5. Remove engine undertray and transmission undertray panels. These are typically secured with Torx fasteners around perimeter.
6. Mark driveshaft-to-differential flange orientation with paint pen for reinstallation alignment reference.
7. Mark both rear axle shaft positions relative to differential output flanges with paint pen for reinstallation reference.
8. Place transmission jack under transmission pan with wooden block or adapter to distribute load. Do NOT apply upward pressure yet.

Procedure

1. 1

   Drain Transmission Fluid
   Position drain pan beneath the rear-mounted transaxle. The ZF 6HP26 uses a fluid level overflow/fill design; follow OEM procedure for draining via the overflow plug on the pan. Verify exact drain plug location and fluid quantity against Aston Martin service documentation before proceeding.g removal. Note: Locate the transmission fill/drain provisions on the ZF 6HP26 transaxle. This unit uses a sealed pan with a level-control (overflow) plug rather than a conventional drain plug; drain fluid per the ZF/Aston Martin fill procedure. Pan drain yields significantly less than total system capacity. Note that additional fluid will drain from the torque converter during removal.
   Torque spec

   Transmission Drain Plug30 Nm (22 lb-ft)
2. 2

   Remove Exhaust System Sections
   Working from rear to front, disconnect exhaust system at appropriate junction to provide clearance for transmission removal. Typically requires disconnecting exhaust at catalytic converter slip joints or center muffler section. Support exhaust with wire or ratchet strap to prevent strain on forward hangers. Remove exhaust hangers as needed to lower exhaust system away from transmission tunnel and driveshaft area. This vehicle uses band clamps or E-Torx fasteners at exhaust joints.
3. 3

   Disconnect Driveshaft
   This vehicle uses a torque tube enclosing the driveshaft between the engine and the rear transaxle. Follow OEM procedure to separate the torque tube from the engine flexplate/clutch coupling and from the transaxle input; there is no separate center bearing or forward slip joint to disengage. Verify torque tube fastener count and sizes against Aston Martin documentation.m vehicle. Inspect center bearing and flex disc for wear during removal. Plug transmission output housing with clean rag to prevent fluid leakage. Note: Disconnect the propshaft per factory procedure (the propshaft runs within the torque tube to the rear transaxle on this platform). Bolt count and E-Torx size must be verified against Aston Martin documentation.
4. 4

   Disconnect Rear Axle Halfshafts
   On each side, remove the inner CV joint flange bolts securing the halfshaft to the final-drive output flange (verify exact count and fastener type against Aston Martin documentation). Support the halfshaft outer end to prevent strain on the outer CV joint and hub bearing. Once bolts are removed, carefully pull the halfshaft away and secure to suspension or chassis. Repeat for opposite side.ng unsupported by outer CV joint alone. Repeat for opposite side. Note: On each side, remove the inner CV joint flange bolts securing the halfshaft to the differential output flange using the appropriate E-Torx socket (bolt count and size per Aston Martin documentation).
5. 5

   Disconnect Transmission Electrical Connections
   Locate main transmission control module connector on driver side of transmission case (typically near valve body area). Depress locking tab and disconnect connector. Disconnect the main mechatronic pass-through connector at the transaxle (the ZF 6HP26 integrates shift solenoids, temperature and speed sensors into the mechatronic module with a single sealed connector). Release the secondary lock before the primary tab, then disconnect any remaining external connectors present. Unclip wiring harness from transmission case routing clips. Some connectors may have secondary locking clips that must be released before primary tab will disengage.
6. 6

   Disconnect Transmission Cooler Lines
   Locate transmission cooler lines where they connect to transmission case (typically on passenger side). Place drain pan beneath connections. These may be quick-disconnect fittings or threaded fittings with spring clips. For quick-disconnect type, depress locking tabs while pulling line straight away from fitting. For threaded type, use appropriate flare nut wrench to prevent rounding. Allow residual fluid to drain. Cap or plug both transmission ports and both lines to prevent contamination.
7. 7

   Remove Shift Cable and Selector Mechanism
   Locate shift cable connection at transmission selector lever (driver side of transmission case). Remove cable retaining clip using small flat screwdriver or pick. Disconnect cable end from selector lever ball stud. Remove cable bracket fasteners (typically 2 Torx or E-Torx bolts) securing cable housing bracket to transmission case. Position cable away from transmission removal path.
8. 8

   Disconnect Starter Motor
   Locate the starter motor at the engine. Disconnect the main power cable from the starter solenoid by removing the retaining nut, then disconnect the trigger wire. Remove the starter mounting bolts (verify count and fastener size against OEM documentation) and remove the starter. Note: on this rear-transaxle vehicle the starter engages the engine ring gear, not a bell-housing-mounted flexplate.fe location. Note: Locate the starter motor at the engine flywheel housing (front of vehicle). NOTE: On this rear-transaxle platform the starter is NOT at the transaxle; verify access path for any converter/flexplate work per factory manual.
9. 9

   Access Torque Converter Bolts
   On this rear-transaxle vehicle the torque converter is housed in the rear transaxle and is not accessed via a front bell-housing starter opening. The engine-end coupling drives the torque tube. Follow OEM procedure to separate the torque tube coupling at the engine and to secure the torque converter within the transaxle. Verify flexplate/coupling bolt count, type, and whether they are single-use against Aston Martin documentation. opening. Remove all torque converter-to-flexplate bolts (quantity per factory documentation) and retain for inspection. These may be TTY (torque-to-yield) bolts requiring replacement. Use magnetic pickup tool to prevent bolts from falling into bell housing. Note: Flexplate retains the torque converter with a set of bolts in a circular pattern (bolt count must be verified against Aston Martin/ZF documentation — commonly 6 on ZF 6HP applications).
10. 10

    Install Engine Support
    Install engine support fixture across engine bay or position overhead crane with leveling sling attached to engine lift points. Typical lift points are threaded bosses on cylinder heads or intake manifold. Apply slight upward tension to engine to preload support and prevent engine from dropping when transmission crossmember is removed. Engine should be level and stable but not lifted off engine mounts at this stage.
11. 11

    Remove Transmission Crossmember
    Locate the transaxle mounting points on the rear subframe. Support the transaxle with a transmission jack. Remove the transaxle mount fasteners and any subframe support fasteners as required (verify exact count, type, and sizes against Aston Martin documentation). Carefully support the transaxle before removing mounts.l using E-Torx sockets). Carefully lower crossmember assembly and remove from vehicle. Transmission is now supported only by bell housing connection and transmission jack. Note: Remove the transaxle/crossmember mounting bolts (quantity and size per Aston Martin documentation) using the appropriate sockets.
12. 12

    Remove Bell Housing to Engine Block Bolts
    This vehicle has no bell-housing-to-engine-block joint; the transaxle is rear-mounted and joined to the engine via a torque tube. Instead, separate the torque tube from the transaxle input and from the engine coupling per OEM procedure. Verify all torque tube and transaxle interface fastener counts and sizes against Aston Martin documentation.ached to bell housing bolts and retain hardware. Note: This vehicle connects the rear transaxle to the engine via a torque tube rather than a bell housing bolted to the block. Disconnect the transaxle from the torque tube per factory procedure; bolt counts and layout differ from a conventional bell housing and must be verified against the Aston Martin Workshop Manual.
13. 13

    Separate and Lower Transmission
    Verify the torque converter is retained in the transaxle. Double-check all electrical connections, cooler lines, and mechanical/torque tube connections are disconnected. After separating the torque tube from the transaxle input, carefully lower the transaxle on the transmission jack and guide it clear of the rear subframe and chassis obstacles. Use an assistant to stabilize the transaxle during lowering. Capture residual fluid in a drain pan.sing from engine. Movement required is approximately 2-3 inches before transmission clears engine block. As transmission separates, torque converter should remain fully seated in transmission pump (approximately 1 inch recess from bell housing face). If converter starts to pull forward, stop and push converter rearward into transmission. Once clear of engine block, carefully tilt front of transmission downward and lower transmission jack while guiding transmission away from vehicle chassis and any remaining obstacles. Use assistant to stabilize transmission during lowering. Residual fluid will drain from converter during tilting; ensure drain pan captures fluid.
14. 14

    Inspect Components
    With transmission removed, inspect the following components for wear or damage: flexplate for cracks or heat damage (especially around bolt holes), torque converter bolts for thread damage or necking (replace if TTY type), pilot bearing/bushing in crankshaft, engine rear main seal for leakage, transmission input shaft seal, transmission pump alignment, and torque converter hub for scoring. Replace flexplate if any cracks are visible. This is optimal time to replace rear main seal if seepage is observed.

Reassembly

1. Before reinstallation, verify torque converter is fully seated in transmission pump by measuring converter depth from bell housing face (should be approximately 1 inch recessed). Test by rotating converter; should rotate freely with slight resistance.
2. Replace all TTY fasteners with new components per parts list. Do not reuse torque converter bolts if they exhibit thread necking.
3. Apply small amount of high-temperature grease to torque converter hub splines and pilot bearing surface.
4. Use alignment dowels to guide transmission onto engine block. Do NOT use bell housing bolts to draw transmission to engine; transmission should slide fully forward with moderate hand pressure only.
5. Tighten bell housing bolts in star pattern, starting with upper bolts. Torque in three stages: initial snug, 50% torque, then final torque.
6. When installing torque converter bolts, use new bolts and apply thread-locking compound per OEM specification. Rotate engine to access each bolt position through starter opening. Torque in star pattern across all 8 bolts.
7. Torque flywheel bolts to specification in star pattern if flexplate was removed. These are critical fasteners.
8. Align driveshaft and halfshaft orientation marks made during disassembly. Failure to align may cause driveline vibration.
9. Refill transmission with correct specification ATF (Touchtronic 6-speed ZF ATF). Initial fill is approximately 9.5 quarts. Check level with engine running in Park after warm-up cycle.
10. After reinstallation is complete, use OBD-II scan tool to clear transmission adaptive values and allow TCM to relearn shift parameters during test drive.
11. Perform transmission adaptation procedure per OEM specification: warm transmission to operating temperature, cycle through all gear positions with 5-second hold in each position, perform multiple moderate acceleration cycles through all gears.
12. Recheck transmission fluid level after test drive and top off as needed. Fluid level must be checked with transmission at operating temperature (160-180°F) and engine running in Park.

Verification

• Before lowering vehicle, verify all electrical connectors are fully seated with locking tabs engaged and all cooler line fittings are secure without leakage.
• With vehicle on ground, start engine and verify no abnormal noises from transmission or bell housing area.
• Check transmission fluid level at operating temperature with engine running in Park. Fluid should be within crosshatch marks on dipstick or within specification on level check procedure.
• Test drive vehicle and verify smooth shifting through all gears under light, moderate, and heavy throttle conditions. First 10-15 shifts may be slightly harsh as TCM relearns adaptive values.
• Verify no fluid leakage from transmission pan, cooler lines, output shaft seal, or bell housing area after test drive.
• Verify no driveline vibration or unusual noises from driveshaft or halfshaft areas. Any vibration indicates misalignment of driveshaft or halfshaft flanges.
• Use OBD-II scan tool to verify no transmission-related fault codes are present after test drive.
• Recheck all fastener torque values after first 50 miles of operation, particularly driveshaft and crossmember bolts.

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