Driveshaft/Rear Final Drive Flange - Balancing
Group: 39Number: 94-01
Date: April 30, 1994
Subject:
Driveshaft/rear final drive flange, balancing
Model(s):
S4, V8 Quattro
all m.y.
If the driveshaft is removed from the rear final drive flange, these components must be balanced when reassembling.
Follow the balancing procedure in this Technical Bulletin to prevent vibration and droning noises from the driveshaft.
CAUTION!
Part numbers are for reference only. Always check with your Parts Dept. for the latest information.
DRIVESHAFT/REAR FINAL DRIVE FLANGE, BALANCING
Note:
^ The driveshaft and rear final drive flange must be balanced very carefully to avoid vibration and droning noises.
^ Check the driveshaft and flange for damage.
^ The driveshaft must be adjusted and centered in the longitudinal direction at the center bearing.
^ If vibration and droning noises occur at higher speeds after the driveshaft has been adjusted it is necessary to balance the connection between the driveshaft and the rear final drive flange
^ Work on the driveshaft with the vehicle on a two-pillar hoist.
^ Always replace bolts between the driveshaft and flange.
^ Before installing the driveshaft, clean the threaded holes in the flange with a tap to remove traces of old locking compound.
^ After measuring, install new base plates (mounting washers) according to the chart.
- Disconnect exhaust system at double clamp -arrows-.
- Remove main muffler and rear muffler from mounting rings.
- Unfasten heat shield above exhaust pipe connection -arrows-, but only loosen the two forward nuts (at left of illustration) and do not remove heat shield
- Remove fuel tank cover -arrows-.
- Remove cross brace -arrows-.
- Remove bolts securing driveshaft to rear final drive.
- Support driveshaft by hanging with wire.
CAUTION!
Only lower the driveshaft far enough to measure the radial runout of the rear final drive flange. The universal joint on the driveshaft can be damaged if the driveshaft is lowered too far.
- Secure universal dial gauge holder VW387 to mounting of rear final drive crossmember.
- Measure radial runout of final drive flange on inside surface of flange -arrow- by turning one rear wheel.
- Mark outside of flange at point where runout is greatest (greatest distance from center axis of flange).
- Remove old marking on flange (if different from new measurement) and mark point of greatest runout on flange.
- Select required balance weight (base plate) from following chart.
Note:
^ Observe color of marking on driveshaft.
^ Base plates are marked with weight category number.
- Install required base plate opposite point of greatest runout.
- Install two base plates, Part No. 441 521 347, in remaining locations.
- Install all other parts removed in reverse sequence.
Note:
^ When installing the driveshaft on the flange, the marking on the flange at The point with the greatest measured runout must be aligned with the marking on the driveshaft.
^ For stress-free alignment of the exhaust system, refer to Repair Manual, Group 26.
Tightening torques:
Driveshaft to rear final drive 55 Nm (41 ft.lb.)
Center driveshaft bearing to body 20 Nm (15 ft.lb.)
Cross brace to crossmember 55 Nm (41 ft.lb.)
Crossmember/final drive 45 Nm (33 ft.lb.)
Fuel tank cover 20 Nm (15 ft.lb.)
Double clamp on exhaust 40 Nm (30 ft.lb.)