Roof - Booming/Pinging Noises
91chevy16
GMC NUMBER: 91-2-100
GROUP: 2 Frame-Bumper-Sheet Metal
DATE: May, 1991
CORPORATE
NUMBER: 162002
SUBJECT: ROOF "BOOM" (OIL CAN) AND/OR "PINGING" NOISES
MODELS: 1991 S/T 4-DOOR UTILITY VEHICLES
Some owners of the above subject vehicles may experience "boom" or "pinging" noises from the roof area. These conditions can occur from insufficient amounts ot roof bow sealer in the bow channels. Lack of sealer can create roof panel "oil canning" against the # 1 andior # 2 roof bows. The "pinging" condition can occur it the outer roof panel contacts either or both ends of the # 1 roof bow.
To correct this condition, it is necessary to install additional sealer in the roof bow channels and at the outboard end of each roof bow.
SERVICE PROCEDURE:
1. Disconnect negative battery cable.
2. Remove sunshades.
3. Remove grab handles.
4. Remove coat hooks.
5. Remove shoulder belt "D" rings attached to "B" and "C" pillars.
6. Remove "B" pillar trim from both sides of the vehicle.
7. Remove dome light cover and housing.
8. Remove upper rear window glass trim and disconnect rear dome/cargo light.
9. Remove upper three rear quarter glass trim fasteners on each side of vehicle to loosen top of rear quarter glass trim.
NOTE: Removal of entire upper rear quarter glass trim is not necessary.
10. If vehicle is equipped with inside spare tire, remove tire.
11. Lower front of headliner below rear view mirror and slide headliner forward as far as possible. Carefully work the rear of the headliner as far left as possible to clear right side of headliner from rear quarter glass trim and remove headliner.
12. To eliminate roof "boom" visually inspect area between top of # 1 and # 2 roof bows and the outer roof panel for any areas sealer expansion did not occur or areas sealer was missed.
13. Gently push upward on the roof panel to separate it away from the roof bow and apply G.M.S. Type B sealer, GM P/N 1052917, or equivalent, in any open areas along the length of the roof bows found during the visual inspection.
If proper sealer expansion and sealer installation was found then it is not necessary to apply sealer, and you may continue to the next step.
NOTE: Care should be taken not to deform the roof panel.
14. To eliminate "pinging" condition, gently push upward on the roof panel over the # 1 roof bow. Apply G.M.S. Sealer Type "B", GM P/N 1052917, or equivalent. to outboard ends (approximately 6" length) filling entire width of bow surface to insulate roof bow from roof panel.
15. Reinstall headliner.
16. Refasten upper three rear quarter glass trim fasteners.
17. Reconnect rear dome/cargo light and reinstall rear window upper trim.
18. Reinstall dome light housing and cover.
19. Reinstall coat hooks.
20. Reinstall "B" pillar trim.
21. Reinstall shoulder belt "D" rings to "B" and "C" pillars.
22. Reinstall grab handles.
23. Reinstall sunshades.
24. Reinstall spare tire, if equipped.
25. Reconnect negative battery cable.
SERVICE PARTS INFORMATION:
Part Number Description
1052917 G.M.S. Sealer Typoe "B"
Parts are currently available from GMSPO.
WARRANTY INFORMATION:
For vehicles repaired under warranty use:
Labor Operation: T7256
Labor Time: 1.0 hr.
Add: 0.1 hr. if necessary to remove interior spare tire (RPO PNV).
NOTE: Labor Operation is coded to base vehicle coverage in the warranty system.