Century Estate Wagon L4-151 2.5L (1985)
Constant Velocity Joint Boot: All Technical Service Bulletins
Drivetrain - Vibration/Clicking/CV Joint Failure
Bulletin 85-4-4
Date July '85
Ref. No. 85-285-4
SUBJECT:
DRIVE AXLE THERMOPLASTIC BOOT SEAL SERVICE
MODELS AFFECTED:
ALL 1985 FRONT-WHEEL-DRIVE MODELS
FIGURE 1 - TORQUE SPECIFICATIONS
The 1985 front-wheel-drive Buicks use new drive axle boot seals. The new stiffer seals have six (6) convolutes while the 1984 seals have three (3)
convolutes. An exception is the use of silicone boot seals (3 convolutes) on the right hand inboard joint of some 1985 models. Boot seal replacement
must be the same type as originally installed. The new seals are held in place by a strap type clamp of which proper installation requires the use of
Kent-Moore clamp tool number J-34773. This tool was shipped to all dealers as part of the 1985 Essential Tool Program. The tool requires the use of an
18"
length half inch flex handle and a foot pound or metric torque wrench.
See figure 1. If the clamp is not adequately tightened, grease could leak from the seal connection or water may intrude past the seal into the joint.
This condition would be recognized by:
1.
During normal servicing of vehicle, grease is found leaking from the axle shaft/boot seal connection.
2.
Customer returns vehicle with complaint of:
a.
vibration
b.
clicking noise
c.
joint failure
If this condition is encountered, the service technician should remove the suspect drive axle assembly from the vehicle using recommended procedures
found in Section 4D of the 1985 Chassis Service Manual and remove the seal and CV joint.
Upon flushing the CV Joint of grease, both joint and axle shaft (in area protected by seal) should be inspected for a rusty appearance. If rust is found in
CV Joint, both joint and seal should be replaced with a seal and CV Joint assembly service kit. If joint is free of rust and seal was leaking grease, remove
any rust found on axle shaft (especially in area of seal clamping) with a hand wire brush and replace seal using the appropriate seal service kit.
Reassemble following procedure in the 1985 Chassis Service Manual.. New torque specifications have been released for crimping the boot clamps. Note
the new specifications in your service manual and on Dealer Service Bulletin 85-4-2.
New torque specifications for boot clamp:
Clamp crimp torque on small end of boot is 136 N-m (100 ft.lbs.)
Clamp crimp torque on large end of boot is 176 N-m (130 ft.lbs.)
