Body - Body Mounts Stripped, Will Not Loosen
INFORMATIONBulletin No.: 10-08-61-001C
Date: March 22, 2013
Subject: Information on Body Mount Bolt Stripped or Will Not Loosen
Models:
2010-2013 Chevrolet Silverado
2010-2013 GMC Sierra
Supercede:
This bulletin is being revised to update the Parts Information section. Please discard Corporate Bulletin Number 10-08-61-001B (Section 08 - Body and Accessories).
The purpose of this bulletin is to provide guidance to GM dealers when performing repairs that involve the removal of the body mount bolts. Technicians may discover that one of the cab mount bolts won't loosen from the vehicle. The bolt may act like the nut is cross-threaded or no longer secured to the floorpan of the vehicle.
The cab mounted cage nut may have bent or broken loose allowing the nut to spin. If the nut is allowed to spin, it may prevent the bolt from loosening. The front cab mount nuts are welded to the body structure and are not involved with this bulletin.
The cage nut assembly must be accessed from inside of the vehicle if this condition occurs. Some of the cage nuts have rectangular access plates in the floor of the passenger compartment. These plates are located above the affected bolt. On extended cab vehicles it is necessary to create access holes in the rear floor area to reach the rear cage nut.
Creating Access Hole (Extended Cab Vehicles Only)
Use the following steps to create an access hole in the rear floor area of extended cab vehicles. This procedure only applies to the rear set of mounting bolts.
Note
This procedure below is for the left side of the vehicle. The procedure and measurements are the same for both the left and right side procedures.
1. Remove the seat located above the affected bolt. Refer to Rear Seat Replacement in SI.
2. Partially remove (pull back) the floor covering (carpet) to expose the seat mounting stud area of the floor.
3. Apply masking tape to the repair area as shown.
4. Using a straight edge, create a line along the inboard side of the seat mounting studs as shown.
5. Measure and mark as shown (A), 10 mm (3/8 in).
6. Find the center point between the two mounting studs as shown. Create a second mark as shown.
7. Use a center punch to create a mark in the sheet metal.
8. Using a 1-1/2 in. hole saw, create an access hole as shown.
9. Service the cab mounting bolt and nut as required.
10. Coat the perimeter of the access hole with RTV Silicone Sealant, GM P/N 12378521 (in Canada, 88901148) or equivalent, to seal the bare edge of the metal.
11. Install the round body plug, GM P/N 25996758. Ensure that the plug is sealed with the silicone sealant.
12. Reinstall the floor covering and seat.
Cage Nut Access Using Rectangular Service Plug
Rectangular service holes have been provided in the floor of the cab to access the cage nut in all other cab mounting bolt locations. The service hole is directly above the cab mount bolt. Use the following steps to remove and replace the service plugs that cover the service hole.
1. Remove the seat located above the affected bolt. Refer to SI for the applicable seat removal steps.
2. Remove the sill trim plate. Refer to Front Side Door Sill Trim Plate Replacement in SI.
3. Partially remove (pull back) the floor covering (carpet) to expose the rectangular service plug.
4. Using a gasket scraper or similar tool, pry off and discard the rectangular floor plug.
5. Service the cab mounting bolt and nut as required.
6. Coat the perimeter of the access hole with RTV Silicone Sealant, GM P/N 12378521 (in Canada, 88901148) or equivalent, to seal the bare edge of the metal.
7. Install the rectangular body plug, GM P/N 15040085 or 15742557. Ensure that the plug is sealed with the silicone sealant.
8. Reinstall the floor covering, sill trim and seat.
Parts Information
Warranty Information
In most cases, this bulletin information will be used when replacing a body mount and should be claimed under labor code E1095 Drivetrain and Front Suspension Frame Insulator Replacement. If this repair is performed while repairing something different, use the labor code associated with that repair.
- Incremental time for this repair should be claimed using Other Labor Hours (OLH).
- The recommended OLH for this repair is 0.3-0.5 hr per bolt.
Disclaimer