Fleetwood V8-368 6.0L VIN 9 FI (1982)
Drive/Propeller Shaft: All Technical Service Bulletins
Driveline - Vibration/Phasing Boom At 55 MPH and Up
Bulletin No.:
T-88-162
File in Group:
4B
Number:
5 Corp. Ref. No.: 814201R
Date:
Aug. '88
SUBJECT:
DRIVELINE VIBRATION AND/OR PHASING BOOM AT 55 MPH AND UP
MODELS AFFECTED: 1982-1984 RWD DE VILLES AND FLEETWOODS 1985-1988 BROUGHAMS
This bulletin supersedes Serviceman Bulletins T-83-110 and T-84-42 which should be destroyed.
Some 1982-1984 RWD DeVilles and Fleetwoods, and 1985-1988 Broughams may experience a condition of a driveline vibration and/or phasing boom
at 55 mph and up. This condition may be caused by a resonant vibration of the rear axle assembly. To repair this condition it is important to perform all
of the following service procedures, in order, for the specific model year being repaired.
NOTE:
The driveline vibration and/or phasing boom may peak at different speeds depending on model year, rear axle ratio, or size.
1.
Refer to Section OA of the appropriate year Cadillac Service Information Manual to determine if the vibration is road speed sensitive. If the
vibration is road speed sensitive, proceed to step II; if not, refer to the appropriate section of the Service Information Manual.
II. Check wheels and tires for radial and lateral runout and for proper balance, refer to Section 3E in the appropriate year Service Information Manual.
III. For 1982-1983 models only: On 7-1/2" axle assembly, install a new pinion flange, P/N 7827670.
FIGURE 1 - CHECKING PINION FLANGE RUNOUT