Engine Cradle - Popping Noise
Number86-2-10 Date 4/86
Subject: ENGINE CRADLE NOISE
ALL 1984-86 6000 MODELS (APPLICABLE TO 1986 MODELS PRIOR TO BREAKPOINTS) AND 1984 PHOENIX MODELS
Oshawa #1
2/7/86 2G2AG19X0G9268024
Tarrytown
1/17/86 1G2AF27X1GT228880
Some 1984-86 6000 models and 1984 Phoenix models may exhibit a popping type noise during braking and acceleration. The popping noise, caused by a fore and aft shifting of the cradle, can be felt as "oil canning" in the floor pan. (The popping noise should not be confused with a "click" or "clunk" felt in the steering wheel -- covered in Pontiac Dealer Service Bulletin 84-3-14. Another similar sounding noise, "crunching," could be caused by loose cradle mount bolts. Torque should be 85 ft.lbs. (115 N-m).
If the noise is still present after tightening the cradle bolts, it can be corrected by installing shims on both rear cradle mount insulators as shown. The intent of this fix is to create an interference fit using shims. Multiple shims may be used if necessary.
Shims may be fabricated from any available steel or brass shim stock. Thickness should be approximately .025" to .040".
The following procedure should be followed when installing shims:
1. Support cradle with a jack stand on the rear cross member.
2. Remove one (1) rear cradle bolt at a time and lower the jack stand enough to remove pressure from the mount.
CAUTION: Damage to the steering intermediate shaft could result if the cradle is lowered more than required to free the mount.
SHIM:
3. Form shim to mount as shown and reinstall mount. Some rubber lube may be required to ease assembly.
4. Reinstall mount bolt. Torque to 85 ft.lbs. (115 N-m).
5. Repeat above procedure on other rear corner.
Labor Operation Number: E1040
Labor Time: .5 hours