Front Subframe: Service and Repair
Subframe
Special tools, testers and auxiliary items required
• Engine Support Bridge (10 - 222 A)
• Support (10 - 222 A /1)
• Testing Mandrel (3393)
• Torque Wrench (V.A.G 1331)
• Torque Wrench (V.A.G 1332)
• Engine/Transmission Jack (V.A.G 1383 A )
Removing
- Support engine entirely with engine support bridge.
- Remove wheel trim cap, remove cover cap on light-alloy wheels (removal hook in vehicle tool kit).
- Remove wheels.
- Secure brake disc with a wheel bolt.
- Remove noise insulation.
Convertible only
- Remove front diagonal brace. Refer to => [ Front or Rear Diagonal Braces ] Rear Suspension.
Continuation for all vehicles
- Before removing subframe, check whether holes - 1 - and - 2 - are aligned using Testing Mandrel (3393).
If this is not the case, an axle alignment must be performed after the carrier is installed.
- Remove nuts - arrows - at transmission mounts if necessary.
- Remove nuts - 1 -.
- On vehicles with headlamp range control, remove the left front level control system sensor. Refer to => [ Vehicle Level Sensor in Vehicles with Automatic Headlamp Vertical Aim Control ] Front Suspension from the control arm.
- Remove ABS speed sensor bolt - 5 -.
- Remove ABS speed sensor wiring from wheel bearing housing bracket.
Vehicles with brake caliper HP-2
- Remove hex bolt - 2 - and remove brake line bracket.
- Remove bolts - 1 - for brake caliper and take off brake caliper.
- Reinstall brake line holder. Reinstall hex bolt - 2 - and tighten.
- Secure brake caliper to body so that the weight of the brake caliper does not stress or damage the brake line.
Continuation for all vehicles
- Remove brake caliper and secure to body so weight of caliper does not stress or damage brake hose or brake line.
To avoid damaging upper control arm joints, wheel bearing housing must be braced against a rebound that is too strong, e.g. using Engine/Transmission Jack (V.A.G 1383 A)
- Remove bolt - 1 -.
- Remove bolt - 4 -.
- Remove bolt - 3 -.
- Loosen guide link/subframe connection.
- Remove tunnel crossmember if necessary. Refer to => [ Tunnel Crossmember ] Service and Repair.
- Place Engine/Transmission Jack (V.A.G 1383 A ) with wooden block under subframe and press lightly against.
- Remove hex bolts - 1 -.
- Remove hex bolts - 2 - and lower rear subframe.
- Remove guide link hex head bolts.
- Remove guide links from subframe.
• In order not to overbend the joints of track control arm and guide control arm, they must be fastened to the body with a tie wire or something like it.
- Remove power steering line - arrow - from bracket.
- Remove bolt - 3 -.
- Loosen hex bolts - 2 - just enough until it is possible to remove the subframe.
Installing
- Insert subframe and install hex bolts - 5 - and - 6 -.
- Insert suspension strut hex bolts at control arm.
- Guide the track control arms and guide links into subframe.
Before tightening the subframe, it must be fixed to the body using Testing Mandrel (3393).
- Holes - 1 - and - 2 - of the subframe and hole - 3 - of the aluminum bracket must line up on both sides.
• Fixing the carrier in this way is a substitute for a subsequent axle alignment only when:
• The sub-frame is removed completely and installed.
• Holes - 1 - and - 2 - lined up before the repair.
- Position hex bolts - 1 - and - 2 -.
- Protect holes in body for mounting Testing Mandrel (3393) against corrosion.
- Install nut - 1 -.
- Install transmission mount nuts - arrows - if necessary.
- Clip cable - arrow - into bracket.
Tightening sequence
• Thread in body can be repaired with thread insert made of wire according to DIN 8140 (Heli-coil). Thread insert must be same length as thread in body.
• Bonded rubber bushings can only be turned to a limited extent. Only tighten threaded connections at control arms if vehicle is in curb weight position => [ Wheel Bearing, Lifting to Curb Weight Position ] Front Suspension.
- Tighten hex bolts - 2 - and - 5 -.
- Tighten hex bolts - 1 -
- Tighten transmission mount nuts - arrows -.
- Tighten bolt - 2 -
- Tighten engine mount nuts - 1 -.
- Tighten control arm hex bolts - 3 -
- Tighten guide link hex bolts
- Tighten coupling rod to the stabilizer bar - 4
- Suspension strut to control arm
- Install tunnel crossmember if necessary. Refer to => [ Tunnel Crossmember ] Service and Repair.
- Tighten ABS speed sensor bolt - 5 -.
- Tighten brake caliper to wheel bearing housing.
- Mount wheels and tighten.
Convertible only
- Install front diagonal brace. Refer to => [ Front or Rear Diagonal Braces ] Rear Suspension.
Continuation for all vehicles
• If the Testing Mandrel (3393) was attached to the body before subframe removal and installation (before tightening bolts), axle alignment does not have to be done.
• If attaching was not performed, axle alignment must be done.
- Perform an axle alignment. Refer to => [ Wheel Alignment ] Wheel Alignment.
Alignment must take place on a VW/Audi recommended alignment stand.