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Service bulletins for the 2021 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.

1649 on file from NHTSA, as of 2026-10-19.

By type

By component

By trouble code

By topic

Bulletins, newest first
PIP60882025-10-24. Service bulletin. UNKNOWN OR OTHER. This PI Addresses a possible solenoid wiring fault and how to inspect the build date to identify
PIT64402025-10-24. Service bulletin. UNKNOWN OR OTHER. The Driver Information Center may display a message of Transport Mode On after the ignition is cycled.
23-NA-2012025-10-21. Service bulletin. SERVICE BRAKES; ELECTRICAL SYSTEM; STEERING. This service bulletin advises the technician of a possible loose ground that may be causing customer concerns of Loss of Steering Assist and/or Loss of Brake Assist and Malfunction Indicator Lamp (MIL) Illuminated.
25-NA-0802025-10-16. Service bulletin. POWER TRAIN. This service bulletin provides a procedure to overhaul the control valve to replace a plate and worn down check ball to correct the customers concern of No Reverse, No Shift Past Third Gear - DTC P2732 Set.
24-NA-2412025-10-16. Service bulletin. ENGINE. This informational bulletin advises the technician of a part number change for long block engines used in the trucks noted.
22-NA-0802025-10-16. Service bulletin. ENGINE. This technical bulletin provides a procedure to replace the camshaft actuator magnet to correct customer concerns of engine related shudder.
N242454441 -032025-10-09. Service campaign. POWER TRAIN. Certain vehicles listed above, may have a condition where the transmission control valve has worn, resulting in a gradual loss of pressure within the valve. The effects can cause harsh shifting, setting a service engine soon message, reduced engine performance or P0747 diagnostic trouble code. Dealers are to install a new control valve body. The repairs will be made at no charge to the customer.
22-NA-1822025-09-27. Service bulletin. POWER TRAIN. This service bulletin advises the technician to check if the transmission cooler lines are twisted to correct customer concerns of Harsh Shift, Shudder, Surge, Stall, Transmission Overheating and/or High Transmission Fluid Temperature.
22-NA-1612025-09-27. Service bulletin. ELECTRICAL SYSTEM; VISIBILITY/WIPER. This informational bulletin provides information for dealers/technicians on power folding mirrors do not fold at the same speed.
PIT5479H2025-09-17. Service bulletin. UNKNOWN OR OTHER. This Preliminary Information communication provides information to the technician about fluid leaking from the brake caliper piston area found during a service of the vehicle. The substance is actually excess assembly grease from the caliper boot and piston.
N2525083412025-09-16. Service campaign. ENGINE. Certain vehicles listed above, may have a condition that could cause the engine coolant control valve to fail an onboard vehicle diagnostic test. If this condition were to occur, the Malfunction Indicator Lamp (Check Engine Light) will illuminate, and a diagnostic trouble code will set. Additionally in some cases, the engine cooling fans may run after the engine is switched off. Dealers are to replace the engine coolant control valve as necessary. The repairs will be made at no charge to the customer.
PIP5865H2025-09-16. Service bulletin. UNKNOWN OR OTHER. This Preliminary information communicates the possibility of DTC P30BF failing on low mile vehicles due to the possibility of the cylinder 1/2 sliding barrel binding on intake camshaft.
135982025-09-10. Other. UNKNOWN OR OTHER. New Vehicle Monitoring Programs Section in IVH
25-NA-1182025-09-10. Service bulletin. FORWARD COLLISION AVOIDANCE: AUTOMATIC EMERGENCY BRAKING. This service bulletin provides information for the technicians to use a Customer Concern Verification sheet to facilitate the questions needing to be answered by the customer regarding Automatic Emergency Braking (AEB) issues.
25-NA-1142025-09-06. Service bulletin. STRUCTURE:BODY. This informational bulletin provides information on Anti-Chip Coating Appearance.
N252510321-022025-09-05. Service campaign. UNKNOWN OR OTHER. Certain vehicles will receive a software update to add to the existing Check Engine Light a Driver Information Center (DIC) warning message if DTC P0016 sets. Dealers will reprogram the Engine Control Module (ECM). Owners who have accepted applicable terms and conditions will have the opportunity to accept these software changes using wireless over-the-air (OTA) technology without having to bring their vehicle to a dealership. Alternatively, owners may have their vehicle serviced at a GM dealer to receive these software updates.
PIP5845B2025-09-05. Service bulletin. UNKNOWN OR OTHER. This P/I is to advise to inspect the stacked plate heat exchanger as possible root cause for any trans concern.
N252510321-012025-08-28. Service campaign. UNKNOWN OR OTHER. Certain vehicles will receive a software update to add to the existing Check Engine Light a Driver Information Center (DIC) warning message if DTC P0016 sets. Dealers will reprogram the Engine Control Module (ECM). Owners who have accepted applicable terms and conditions will have the opportunity to accept these software changes using wireless over-the-air (OTA) technology without having to bring their vehicle to a dealership. Alternatively, owners may have their vehicle serviced at a GM dealer to receive these software updates.
PIP5865G2025-08-26. Service bulletin. UNKNOWN OR OTHER. This Preliminary information communicates the possibility of DTC P30BF failing on low mile vehicles due to the possibility of the cylinder 1/2 sliding barrel binding on intake camshaft.
PIP5865F2025-08-22. Service bulletin. UNKNOWN OR OTHER. This Preliminary information communicates the possibility of DTC P30BF failing on low mile vehicles due to the possibility of the cylinder 1/2 sliding barrel binding on intake camshaft.
PIP4902T2025-08-22. Service bulletin. UNKNOWN OR OTHER. This preliminary information advises a dealer on how to email GDS2 session logs into Technical Assistance.
PIT6396A2025-08-22. Service bulletin. UNKNOWN OR OTHER. This PI communicates an issue with a SES MIL with DTC P2535, P12A6, P10DA and/or C111B maybe set after replacing the fuel pump driver module. Engineering is working on a fix, but in the meantime, dealers are to install a diode.
N2525103212025-08-14. Service campaign. UNKNOWN OR OTHER. Certain vehicles will receive a software update to add to the existing Check Engine Light a Driver Information Center (DIC) warning message if DTC P0016 sets. Dealers will reprogram the Engine Control Module (ECM). Owners who have accepted applicable terms and conditions will have the opportunity to accept these software changes using wireless over-the-air (OTA) technology without having to bring their vehicle to a dealership. Alternatively, owners may have their vehicle serviced at a GM dealer to receive these software updates.
PIC5650M2025-08-12. Service bulletin. UNKNOWN OR OTHER. This Preliminary Information communication provides information to the technician about vehicles that have an intermittent no crank, no start, or start stall concern with the security light coming on. Technician may find Diagnostic Trouble Codes B3055, B3060, B3935, C0750, C0755, C0760, C0765, and/or C0775.
PIT5161L2025-08-04. Service bulletin. UNKNOWN OR OTHER. This Preliminary Information communication provides information to the technician about vehicles that may have a bump feel or clunk noise at a stop or on launch. Dealer should communicate to the customer this condition is a normal operating characteristic

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