420519 Removing and installing rear axle housing (chassis subframe)
WM 420519 Removing and installing rear axle housing (chassis subframe)
Tools
Preliminary work
1. Raise the vehicle. -> 4X00IN Lifting the vehicle Service and Repair
2. Remove rear wheels. -> 440519 Removing and installing wheel Removal and Replacement
3. Bleed the air springs on vehicles with air suspension. -> 4301IN Bleeding and filling the levelling system 4301IN Bleeding and filling the levelling system
4. Remove the steel springs on vehicles with steel suspension. -> 427219 Removing and installing rear coil springs
5. Remove rear left wheel housing liner. -> 536919 Removing and installing rear wheel housing liner Service and Repair
6. Remove underbody panelling. -> 519319 Removing and installing cover for centre underbody 519319 Removing and Installing Cover for Centre Underbody-> 519419 Removing and installing cover for rear underbody 519419 Removing and Installing Cover for Rear Underbody
7. Remove the exhaust system starting at the connection point after the catalytic converter. -> 260119 Removing and installing exhaust system Service and Repair
8. Remove the cardan shaft.
8.1. Mark the installation position of the cardan shaft -arrow-.
8.2. Remove the cardan shaft -> 393519 Removing and installing rear cardan shaft Service and Repair
Marking for cardan shaft (example)
Tools and materials
Master Gear unit elevating platform WE 1206
Only the supports marked with double digits (e.g. P11, P22) are used for mounting the rear axle!
Lifting platform
Loosening tool 9780
Removing
Removing rear axle housing
WARNING
Wheel bearing housing raised incorrectly
- Risk of squashing
- Risk of damage to components
-> Wear personal protective gear.
-> Do not raise the wheel suspension higher than the normal vehicle position (vehicle resting on wheels).
WARNING
Caustic fluids
- Danger of chemical burns
-> Avoid contact with caustic fluid.
-> Wear personal protective gear.
-> Ensure that there is good ventilation.
-> If you do come into contact, wash off immediately with plenty of warm water and contact a doctor if necessary.
NOTICE
Aggressive fluids
- Risk of damage to components and surfaces
-> Do not spill fluids.
-> In the event of contact, wash the component or surface with water.
-> Replace components that are already damaged.
Information
Working with steel flexi-pipes
- Steel flexi-pipes are particularly prone to kinking and pinching.
- Be particularly careful with steel flexi-pipes during removal, storage and reinstallation.
- Mark the installation position of the pipe with a paint marker during removal.
- Steel flexi-pipes must never be installed twisted.
Rear axle housing, component
1. Remove the required covers from the side panel in the luggage compartment. => Removing cover in side panel (left side shown)
Removing cover in side panel (left side shown)
1.1. Carefully pull off the connector for PASM -arrow-.
Removing PASM connector
2. Only remove vibration damper at the top! -> 429319 Removing and installing rear shock absorber (spring damper) 429319 Removing and installing rear shock absorber (spring damper)
3. Release brake caliper (do not open the brake system!) and hang it at a suitable position in the wheel housing.
4. Unclip rear left combination connector on the left anti-roll-bar mount.
5. Unclip rear left combination connector on the PDCC valve block holder.
6. Unclip rear right combination connector (PU part) on the right anti-roll-bar mount.
7. Unclip the two connectors (differential lock and valve block for air suspension) at the right on the rear axle housing in front of the anti-roll bar.
8. Loosen all connections on the compressor except the fastening screws. -> 431519 Removing and installing compressor for level control system Service and Repair
9. Mark the position of the rear axle housing (chassis subframe) on the body (to facilitate assembly).
9.1. This marking must be applied to at least the two front bolting points on the rear axle housing (chassis subframe). This gives a rough idea of the correct position for reinstallation.
9.2. Mark the installation position of the rear-axle housing on at least two places on the body using a felt-tip pen for example. Make the marks with respect to the floor of the body (e.g. mark along the rear axle housing mount with the pen) => Marking (example).
Marking (example)
10. Disconnect air-spring connections -arrows- and close them off using suitable stoppers.
10.1. Unclip the air springs at the top and pull them down. They remain on the trailing arms during removal.
Disconnecting air-spring connections
Information
Collect power-steering fluid.
- Before loosening the pressure and return lines (also PDCC), place a suitable container underneath to collect power-steering fluid.
- Wear protective goggles and gloves.
11. Disconnect PDCC lines in front of the left wheel housing using loosening tool 9780.
12. Lift the rear axle housing using the Master Gear unit elevating platform WE 1206.
12.1. Jacking points for the assembly frame in the rear axle housing (view from below here) -arrows-.
Rear axle housing (example)
12.2. Place elevating platform Master Gear unit elevating platform WE 1206 under the vehicle and move all assembly drivers to the same height at the correct position. Guide into the jacking points provided for this purpose => Rear axle and elevating platform (example).
Rear axle and elevating platform (example)
Information
- Before moving the lifting platform, mark the position of the wheels on the workshop floor with a piece of chalk. This makes it easier to position the platform again for re-installation.
13. Remove the mounting elements from the rear axle housing and carefully remove the axle without hitting against adjacent components.
Information
If you are replacing the rear axle housing (chassis subframe), the accessories must also be converted as required following a visual inspection.
Replace rear axle housing
Install at the correct position and check that all accessories are installed. Document installation by taking photos if necessary (installation aid!).
- Remove air springs (unclip at the bottom)
- Remove compressor
- Remove longitudinal support
- Remove anti-roll bar
- Remove PDCC valve block and holder
- Remove rear axle differential
- Remove level sensors
- Press out the drive shafts on the rear axle differential and set them down carefully. Use a protective tube (shop-made). -> 422119 Removing and installing rear drive shaft 422119 Removing and installing rear drive shaft
- Remove vibration damper
- Remove wheel bearing housing with upper/lower trailing arms and drive shaft. A second worker is required!
- Remove wiring harnesses. Check that the wiring harnesses are routed correctly! Document installation by taking photos if necessary (installation aid!).
Installing
Installing rear axle housing
WARNING
Wheel bearing housing raised incorrectly
- Risk of squashing
- Risk of damage to components
-> Wear personal protective gear.
-> Do not raise the wheel suspension higher than the normal vehicle position (vehicle resting on wheels).
WARNING
Caustic fluids
- Danger of chemical burns
-> Avoid contact with caustic fluid.
-> Wear personal protective gear.
-> Ensure that there is good ventilation.
-> If you do come into contact, wash off immediately with plenty of warm water and contact a doctor if necessary.
NOTICE
Aggressive fluids
- Risk of damage to components and surfaces
-> Do not spill fluids.
-> In the event of contact, wash the component or surface with water.
-> Replace components that are already damaged.
Information
- All the threaded joints on the axle must be tightened in vehicle position. Vehicle position means: vehicle standing on its wheels, or the wheel suspension is raised using a universal vehicle lift. Dimension -X- , from lower edge of wing to middle of axle corresponds to vehicle position. For details of current height values, see -> 4495TW Adjustment values for wheel alignment Specifications . Always observe the following points!
Dimension X - centre of wheel to lower edge of wing (rear axle shown)
Steel springs
- The vehicle position is reached at the front axle by placing the vehicle onto the wheels in a suitable work area (wheel alignment platform, workshop pit).
Air suspension
- The vehicle position is reached at the front axle with air suspension by bleeding the respective air spring using the Porsche System Tester and carefully lifting the respective wheel bearing housing.
- Use an intermediate layer (hard rubber)! Do not damage the brake cover plate.
Raising wheel carrier, front axle (example)
- Screws and nuts are Geomet-coated and must not be greased.
- Grease the toothing of the drive shaft slightly with aluminium paste Optimoly TA.
- Drive shafts must not be left hanging from the joint stop! Tie up.
- Use new screws and lock nuts.
- Use correct tightening torques and torque angles. -> 4X00IN00 Tightening torques for front axle
Installation is performed in reverse order.
Check that the wiring harnesses are routed correctly!
Subsequent work
1. Fit cardan shaft. -> 393519 Removing and installing rear cardan shaft Service and Repair
2. Fit exhaust system. -> 260119 Removing and installing exhaust system Service and Repair
3. Bleed the air springs on vehicles with air suspension. -> 4301IN Bleeding and filling the levelling system 4301IN Bleeding and filling the levelling system
4. Fit the steel springs on vehicles with steel suspension. -> 427219 Removing and installing rear coil springs
5. Bleed the PDCC system on vehicles with PDCC. -> 430307 Bleeding Porsche Dynamic Chassis Control (PDCC) 430307 Bleeding Porsche Dynamic Chassis Control (PDCC)
6. Install rear left wheel housing liner. -> 536919 Removing and installing rear wheel housing liner Service and Repair
7. Fit underbody panelling. -> 519319 Removing and installing cover for centre underbody 519319 Removing and Installing Cover for Centre Underbody-> 519419 Removing and installing cover for rear underbody 519419 Removing and Installing Cover for Rear Underbody
8. Fit rear wheels. -> 440519 Removing and installing wheel Removal and Replacement
9. Press the brake pedal if necessary in order to position the pads.
10. Read out and erase the fault memory using PIWIS Tester II 9818.
11. Perform suspension alignment. -> 449503 Suspension alignment, complete 449503 Suspension Alignment, Complete