Bulletin No.: 10-08-61-001B
Date: Jan-2013

Subject:

Information on Body Mount Bolt Stripped or Will Not Loosen

Models:

2010-2013 Chevrolet Silverado
2010-2013 GMC Sierra

This bulletin is being revised to add the 2012-2013 model years and Parts Information. Please discard Corporate Bulletin
Number 10-08-61-001A (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.

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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.

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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.

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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. Ensure that the plug is sealed with the silicone sealant.

8.

Reinstall the floor covering, sill trim and seat.

Parts Information

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Part Number

Description

Qty

15040085

Plug, Floor Panel Drain Hole
(Rectangular Style Plug)

As
Req.

25996758

Plug, Floor Panel Drain Hole (Round
Style Plug)

As
Req.

12378521 (in
Canada,
88901148)

RTV Silicone Sealant

As
Req

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.

GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these technicians of conditions that may
occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools,
safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that
your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information.

WE SUPPORT VOLUNTARY TECHNICIAN CERTIFICATION

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