GMC Chevrolet Camaro 1998 Service Manual page 87

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General Information
6. Once the propeller shaft and pinion flange are
within runout tolerances, check if the vibration is
gone. If the level of the vibration is still .
unacceptable, perform a driveline system balance
procedure.
Correcting Vibration at the Transmission
Tailshaft
First-order c;iriveline vibrations that originate at the
transmission end of the propeller shaft are rare. If the
tailshaft of the transmission is vibrating, inspect the
tailshaft housing bushing for wear or damage. A leaky
transmission tailshaft oil seal indicates bushing
problems.
Feel for vibration at the crossmember underneath the
transmission mount. If there is no vibration, the
transmission mount is doing its job of isolating the
vibration from the structure of the vehide. The
transmission mount is therefore probably not cause of
vibration.
Use the following procedure if you can feel vibration
on the crossmember and the tailshaft bushing,
and if transmission output is normal:
1 . Measure the propeller shaft runout. If the runout is
excessive, replace the shaft with one that has
acceptable runout. Alternatively, sublet the shaft
to a reputable independent service. shop in
order to have the shaft rebalanced and the runout
corrected.
2. Test drive the vehicle. If the vibration is still
unacceptable, balance the propeller shaft on
the vehicle.
Correcting Vibration at the Center Support
Bearing
These guidelines apply to the two-piece propeller shaft
only. First-order driveline vibrations that occur mainly
at the center support bearing (2) are usually the result
of excessive runout at the stub (splined) shaft (3).
Unlike other first-order driveline vibrations, these
vibrations can appear at unusually low speeds of
40 km/h (25 mph) and up.
Follow the following procedure to correct this type of
vibration:
1 . Mark the position of the rear propeller shaft at
both ends for proper reassembly. Remove the
rear propeller shaft form the vehicle.
2. Measure the runout of the splines about 12.7 mm
(0.5
in) from the end (1 ).
3. Replace the shaft if the runout exceeds the
tolerances.
Stub shafVspline runout 0.076 mm (0.003 in)
Vibration Diagnosis .and Correction 0-75
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