BMW 5251 Service Manual page 610

1
Driveshaft
Further inspection requires removal of the driveshaft. Checlc
the front centering guide on the transmission output flange for
damage or misalignment. Also check runout at the transmis-
sion output fiange and output shaft, and at the final drive input
fiange. Check the bolt hole bores in the flange for wear and
elongation.
Driveshaft flange runout (max. allowable)
Transmission flange
-
Axial play
0.10 mm (0.004 in.)
Radial play 0.07 mm (0.003 in.)
Spin the driveshaft center bearing and check ior smooth op-
eration without play. Check the constant velocity joint forwear
or play. Checlc the universal joint for wear or binding. If it is
difficult to move or binds, the driveshaft section should be
replaced.
Universal joint
play
Maximum allowable
0.15 mm (0.006 in.)
NOTE-
With the driveshaft installed, the actual amount that the drive-
shaftjoint pivots is limited. For the most accurate test, check
joint
in
its normal range of movement.
If inspection reveals nothing wrong with the driveshaft, it may
need to be rebalanced. This can be done by a speciality drive-
shaft repair shop. Also, checlc driveshaft alignment as de-
scribed below.
NOTE-
Minor driveshaft vibrations can often be corrected simply by
disconnecting the driveshaft at the final drive and reposition-
ing it go", 180" or 270" in relation to the final drive input
flange.
The troubleshooting table below lists symptoms oi driveshaft
problems and their probable causes. Most of the repair infor-
mation is contained within this repair group. There are refer-
ences to other repair groups, where applicable.