Overhaul

Air Spring Shock Absorber

• Observe the information regarding air spring shock absorber repair. Refer to => [ Air Spring Damper Repair Information ] Air Spring Damper Repair Information.

Special tools, testers and auxiliary items required

• Special Socket Wrench 21 mm (3186)

• Guide Rods (T10093)

• Torque Wrench (V.A.G 1332)

• Spring Compressor (V.A.G 1752/1)

• Holding Fixture for Suspension Struts (V.A.G 1752/20)

• Spring Holder (V.A.G 1752/3A)

• Spring Holder (V.A.G 1752/7)

• Release Tool Set (VAS 1978/35)

• Disassembly Wedge (3409)

• Vehicle Diagnostic Tester (VAS 5051B)

Perform the Following Work:






- Remove the air spring damper. Refer to => [ Air Spring Damper ] Rear Suspension.

• Check whether the air spring is still filled with a residual pressure of 3 bar.

• Press with the thumbs on the air spring bead. The bead must demonstrate noticeable resistance.

• If significant resistance is not noticed, the air spring is not pressurized.

Disassembling

- Pull the boot downward off of the shock absorber and remove.

- Tension the (V.A.G 1752/20) - 1 - in a vice.






- Tension the air spring shock absorber in the (V.A.G 1752/20) - 1 -.

- Eject the cable sockets from the air spring shock absorber connector with the (VAS 1978/35).

- Unclip the cable guide - 3 -.

- Remove the grommet - arrow - from the cover - 2 -.






- Unscrew the bolts - 1 - and remove the cover - 2 -.

- Conduct the cable through the grommet.

- Unscrew the nut from the mount while counterholding at the hex fitting - 3 -.






1. Commercially available ratchet

2. (3186)


- Remove the mount from the shock absorber.

- Insert the (T10093) - 1 - into the air spring shock absorber mount.






• The (T10093) acts as a counterhold for the (V.A.G 1752/3A) - 2 -.

• To prevent damage, insert a rubber mat - 6 - or similar protection between the (V.A.G 1752/7) - 5 - and the rolling piston.

- Press the air spring rolling piston - 1 - off the shock absorber using the (V.A.G 1752/1).

1. (T10093)

2. (V.A.G 1752/3A)

3. (V.A.G 1752/20)

4. Rolling piston

5. (V.A.G 1752/7)

6. Rubber mat or similar item

7. Outer guide

8. (V.A.G 1752/1)


• Insert protective material such as rubber between the (V.A.G 1752/7) and rolling piston.

• Insert protective material such as rubber between the (V.A.G 1752/3A) and shock absorber.

• Make sure that the rolling piston - 4 - does not slip down out of the outer guide - 7 -.

• If air spring is reused and air spring has slipped out of outer guide, it must be slid in again by forming even circumferential folds on the rolling bellows - arrows -.






Assembling






- If the shock absorber was not replaced, the sealing rings - arrows - at the piston rod and the shock absorber tube must be replaced.

- Clean the contact surface with a lint-free cloth.

• Even the smallest amount of contamination leads to air spring shock absorber leaks.

- Lightly lubricate the sealing rings with (N 052 150 00).

- Slide the anti-extraction device onto the shock absorber tube.

• If air spring is reused and air spring has slipped out of outer guide, it must be slid in again by forming even circumferential folds on the rolling bellows - arrows -.






- Extend the shock absorber line, e.g. with a cable, so that it can be routed through the air spring.

- Ensure that the buffer stop - 1 - is seated properly in the cover - 2 - - arrow -.






The large diameter of the buffer stop - 1 - must clamp in the cover - 2 -.

- Install the mount and secure it with a new nut while counterholding at the hex fitting - 3 -.






1. Commercially available ratchet

2. (3186)


- Insert the cable socket in the connector housing.

- Reinstall the cable guide - 3 - and clip.

- Install the cover - 2 - and secure with the bolts - 1 -.






- Insert the grommets - arrows - in the cover - 2 -.

- °Align the air spring so that the pressure-holding valve - 1 - is located near the imaginary axis of symmetry - arrow - (approximately 10 offset from the center) on the air spring shock absorber.






• Only rotate at the rolling piston - Item 7 - => [ (Item 7) Rolling Piston ] Rear Air Spring Damper Components in order to avoid damaging the rolling bellows - Item 6 - => [ (Item 6) Boot ] Rear Air Spring Damper Components inside the air spring.

- Install the air springs but do not connect the air line yet. Refer to => [ Air Spring Damper ] Rear Suspension.

- Using the (V.A.G 1383 A) , raise the air spring shock absorber until the piston - 1 - is lying on the anti-extraction device - arrow -.






- Press the anti-extraction device into the piston using the (3409).






1. (3409)


- Continue lifting the air spring shock absorber using the (V.A.G 1383 A) until the welded ring on the shock absorber tube is approximately 3 mm inside the extraction piston - arrow -.






- When draining, hold the pressure retaining open by opening the valve plunger with a 5 mm hex wrench so that the air can flow through.

• This will prevent the dust boot from creasing.

- Slide the boot onto the air spring.

- Slide the boot over the shock absorber so that the boot groove engages.

The rear air line is covered with shrinkable tubing.






- Insert the air line until the end of the shrinkable tubing - 2 - is in contact with the union nut - 1 -.

The end of the shrinkable tubing may be a maximum of 2 mm in front of the union nut.

- Screw on the air line with the union nut - 1 - at the air spring shock absorber.






- Fill the rear air spring shock absorber using the (VAS 5051B).

- Install the wheel and tighten the wheel bolts. Refer to => [ Wheel Bolt Torque Specification ] [1][2]Specifications.

Tightening Specifications