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Service bulletins for the 2012 GMC Sierra

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

2268 on file from NHTSA, as of 2026-10-19.

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Only bulletins with component: Trailer hitch are shown. Show all

Bulletins, newest first
PIT4729E2023-11-20. Service bulletin. SERVICE BRAKES; TRAILER HITCHES. Adding Integrated Trailer Brake Controller RPO JL1.
PIT5432B2018-06-18. Service bulletin. EQUIPMENT; TRAILER HITCHES:FIFTH WHEEL ASSEMBLY. This Preliminary Information communication provides information to the technician about vehicles that have a Shudder, bounce, bucking from the rear of the truck while braking when towing a gooseneck or fifth wheel trailer. Technician will need to measure the actual truck and trailer weights, with the trailer loaded to the point that exhibits the condition. If any weight parameter is exceeded such as the Front Gross Axle Weight Rating, Rear Gross Axle Weight Rating, Gross Vehicle Weight Rating, or Gross Combined Weight Rating the load must be reduced before investigating further. If evaluation of the trailer’s brakes indicates trailer brake capability is adequate, adjust brake controller per the Trailer Gain Adjustment Procedure described in the Driving and Operating section of the Owner’s Manual and evaluate truck and trailer combination for braking shudder.
PIT4729E2017-08-15. Service bulletin. ELECTRICAL SYSTEM: INTEGRATED TRAILER BRAKE CONTROL; TRAILER HITCHES. This Preliminary Information communication provides information to the technician about customer's wanting to add the factory Integrated Trailer Brake Controller Regular Production Option Code (JL1) be installed on their Full Size pickup/utility when the vehicle was not ordered with the option. Dealer should advise the customer that if the vehicle does not have the option Regular Production Option Code (JL1) it cannot be added to the vehicle.
PIT4366G2017-08-15. Service bulletin. ELECTRICAL SYSTEM; ELECTRICAL SYSTEM: INTEGRATED TRAILER BRAKE CONTROL; TRAILER HITCHES. This Preliminary Information communication provides information to the technician on the steps to diagnose and repair vehicles that may have an intermittent "Check Trailer Wiring" message on the Driver Information Center. Technician will inspect and clean the ground wire (normally white wire) connection on the trailer side of the 7-pin connector. Inspect that the wires inside the trailer side connector are clean and securely fastened. If the vehicle's 7-way connector socket terminals are deformed or have excessive wear, it will be necessary to replace the truck side connector from General Motors Customer Care and Aftersales along with the trailer's 7-way connector plug.

The summaries are NHTSA's. Each bulletin's page links NHTSA's copy of the manufacturer's document.