Subframe
Subframe
Special tools, testers and auxiliary items required
• Torque wrench (5-50 Nm) (VAG 1331)
• Torque wrench (40-200 Nm) (VAG 1332)
• Engine and transmission jack (VAG 1383A) with universal transmission support (VAG 1359/2)
• M10 x 100 (strength category 10.9) bolt
Removing
• The steps show how to remove the subframe as a complete unit (for example, with the rear final drive, stub axle carrier/wheel bearing housing, trailing arm, etc.).
• Measure the vehicle after repair.=> [ Vehicle Alignment Overview ] Vehicle Alignment Overview.
CAUTION!
Before loosening the subframe bolts make sure the vehicle does not sit at an angle (for example, load the luggage compartment with at least 100 kg).
- Place the vehicle on a hoist. Refer to => [ Positioning Vehicle on the Hoist and on its Wheels ] Positioning Vehicle on the Hoist and on its Wheels.
Perform the following steps on the left and right sides.
Please note
- Loosen the bolt - arrow - first if:
• The drive axle will be replaced
• or other component will be replaced that require the bolt to be removed.
CAUTION!
When loosening and tightening the bolt, vehicle must sit on its wheels.
-risk of accident-
- Remove the wheel covers, remove the cover cap on light alloy wheels (removal hook in vehicle tool kit).
- Remove the wheel.
- Secure the brake disc with a wheel bolt.
- Remove the wheel housing liner.
- Clean the air spring damper air connection area.
- Remove the connecting piece - 1 - from the residual pressure valve - 2 -. Air then escapes.
• Generally, the residual pressure valve - 2 - must not be loosened or removed.
- Seal both connections. Make sure that no dust particles enter the connections.
- Remove the brake caliper wiring harness electrical connector - 1 - from the retainer and disconnect it.
- Disconnect the electrical connector - 2 - from the speed sensor.
- Remove the brake caliper and secure it to the body.
• Secure the brake caliper to the body with wire.
• Do not allow the brake caliper to hang from the brake line.
- Remove the bolts - 1 through 3 - from the cover plate - 4 - and remove the cover plate.
- Disconnect the level control system sensor electrical connector - 1 -.
- Remove the brake line bracket - 2 -.
- Remove the coupling rod bolt - 1 - and disengage the brake line bracket - 2 -.
- Tilt the coupling rod back.
- Remove the bolts - 1 - for the wire channel - 2 -.
- Remove the air spring damper on the track control arm and tilt it back (control position). Refer to => [ Wheel Bearing Housing, Raising to Control Position to Tighten Bolts ] Procedures.
- Remove the exhaust system lines - 4 -.
- Remove the rear portion of the exhaust system. Remove the bolts - 1 through 3 - and the exhaust system (a second technician is needed).
- Remove the air duct bolts - arrows - on the rear final drive and remove the air duct, if equipped.
- Before removing the driveshaft - 1 - from the rear final drive, support it with a wood block on the crossmember - 2 -.
- Mark the position of the driveshaft to the rear final drive with paint.
- Install the M10 x 100 (strength category 10.9) bolt - 3 - in the rear final drive.
- To loosen the bolts - 1 -, counter hold the driveshaft using a pry bar - 2 -.
- Remove the driveshaft bolts - 1 -.
- Place the (VAG 1383A) with the (VAG 1359/2) under the subframe with the rear final drive.
- Secure the subframe with the rear final drive to the (VAG 1359/2) so it does not fall off.
If applicable,
- Remove the subframe bolts - 2 -, the bolts - 3 - and the subframe support - 1 -.
Continuation for All Vehicles
- Remove the subframe bolts - 1 through 4 -.
- Lower the subframe carefully. Guide the brake caliper - arrows - through the suspension.
Installing
Installation is performed in the reverse order of removal. Observe the following when doing so:
- Tighten the bolts/nuts on components with bonded rubber bushings by hand. Raise the wheel bearing housing to tighten the bolts/nuts. Refer to => [ Wheel Bearing Housing, Raising to Control Position to Tighten Bolts ] Procedures.
- Place the subframe with the rear final drive on the (VAG 1383A) with the (VAG 1359/2).
- Secure the subframe with the rear final drive to the (VAG 1359/2) so it does not fall off.
- Raise the subframe carefully. Guide the brake caliper - arrows - through the suspension.
- Center the subframe over the four bearing holes to body.
If applicable,
- Position the support - 1 - and tighten the subframe bolts - 2 - and bolts - 3 - by hand.
Continuation for All Vehicles
- Note the location of the tension discs - 2 and 3 -, refer to - item 7 - in => [ Subframe Assembly Overview ] Service and Repair.
- Install the subframe bolts - 1 through 4 - with new washers.
- Tighten the bolts - 1 through 4 - to the specification with no additional turn. Refer to - item 30 - in => [ Subframe Assembly Overview ] Service and Repair.
Only tighten the bolts - 1 through 4 - to the specification with an additional turn after the vehicle alignment. Refer to => [ Wheel Alignment ] Wheel Alignment.
- Install the driveshaft to the rear final drive.
- Position the air duct on the rear final drive and tighten the bolts - arrows -, if equipped.
- Install and align the exhaust system.
- Position and install the bolts - 1 - for the wire channel- 2 -. Refer to - item 11 - in => [ Subframe Assembly Overview ] Service and Repair.
- Connect the level control system sensor connector - 1 -.
- Install the brake line bracket - 2 -. Refer to - item 29 - in => [ Stabilizer Bar, Track Control Arm, Tie Rod, Coupling Rod, Connecting Link, Trailing Arm and Level Control System Sensor Assembly Overview ] Stabilizer Bar, Track Control Arm, Tie Rod, Coupling Rod, Connecting Link, Trailing Arm and Level Control System Sensor Assembl.
- Tighten the cover plate - 4 - with the bolts - 1 through 3 -. Refer to - item 9 - in => [ Air Spring Damper, Wheel Bearing Housing and Wheel Hub and Bearing Assembly Overview ] Rear Suspension.
• The bolts - 2 and 3 - secure the wiring harness bracket located behind the cover plate to the wheel bearing housing.
- Install the brake caliper.
- Install the brake line bracket - 2 - and tighten the coupling rod bolt - 1 -. Refer to - item 25 - in => [ Stabilizer Bar, Track Control Arm, Tie Rod, Coupling Rod, Connecting Link, Trailing Arm and Level Control System Sensor Assembly Overview ] Stabilizer Bar, Track Control Arm, Tie Rod, Coupling Rod, Connecting Link, Trailing Arm and Level Control System Sensor Assembl.
The wheel bearing housing must be lifted into the control position to install and tighten the bolts. Refer to => [ Wheel Bearing Housing, Raising to Control Position to Tighten Bolts ] Procedures.
- Connect the electrical connector - 2 - to the speed sensor.
- Insert the brake caliper connector - 1 - into the retainer and connect it.
- Tighten the connecting piece - 1 - to the residual pressure retaining valve - 2 -. Refer to - item 37 - in => [ Air Spring Damper, Wheel Bearing Housing and Wheel Hub and Bearing Assembly Overview ] Rear Suspension.
- Install the wheel housing liner.
- Install the level control system sensor bolt - 1 -. Refer to - item 28 - in => [ Subframe Assembly Overview ] Service and Repair. The sensor lever must face inward.
- Push the wheel bearing housing down by hand and install the bolt - 4 - in the air spring damper/trailing arm.
- Only tighten the nut - 3 - by hand.
- Install the wheel and tighten.
- Place vehicle on its wheels. Refer to => [ Positioning Vehicle on the Hoist and on its Wheels ] Positioning Vehicle on the Hoist and on its Wheels.
- Tighten the bolt - 4 - with the vehicle at the "standard level" and resting on the floor. Refer to - item 6 - in => [ Stabilizer Bar, Track Control Arm, Tie Rod, Coupling Rod, Connecting Link, Trailing Arm and Level Control System Sensor Assembly Overview ] Stabilizer Bar, Track Control Arm, Tie Rod, Coupling Rod, Connecting Link, Trailing Arm and Level Control System Sensor Assembl. Counter hold the nut - 3 - when doing this.
Only when you have loosed the drive axle bolt:
Always use a new drive axle bolt!
- Tighten the drive axle bolt. Refer to => [ Installing ] Drive Axle.
- Perform a vehicle alignment. Refer to => [ Wheel Alignment ] Wheel Alignment.
- Tighten the subframe bolts - 1 through 4 - to the specification with the additional turn. Refer to - items 8 or 30 - in => [ Subframe Assembly Overview ] Service and Repair.
- Readapt the control position. Refer to => [ Control Position, Programming ] Level Control System.