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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
20-NA-0822023-09-06. Service bulletin. FUEL SYSTEM, DIESEL; ENGINE AND ENGINE COOLING:ENGINE:DIESEL. This informational bulletin explains why more DEF is being used in diesel engines due to new emission standards.
18-NA-1032023-09-01. Service bulletin. ELECTRICAL SYSTEM; FUEL SYSTEM, DIESEL. This service bulletin provides service information for customer concerns of an in-tank fuel pump whining noise, engine hard to start and/or stalls and Malfunction Indicator Lamp (MIL) is illuminated that may be caused by gelling of fuel in cold temperatures.
16-NA-2442023-09-01. Service bulletin. ENGINE AND ENGINE COOLING; FUEL SYSTEM, DIESEL. This informational bulletin provides information on Diesel Exhaust Fluid (DEF) and the proper use of the DEF system.
10-06-05-002M2023-08-28. Service bulletin. FUEL SYSTEM, DIESEL; ENGINE AND ENGINE COOLING:EXHAUST SYSTEM. This informational bulletin provides information on Clean Exhaust Filter See Owner Manual Now or Cleaning Exhaust Filter Keep Driving Until Message is Cleared messages Displayed on DIC, DTC P2463 May Be Set.
04-06-04-051H2023-08-28. Service bulletin. ENGINE AND ENGINE COOLING; FUEL SYSTEM, GASOLINE. This service bulletin provides information for maintenance cleaning of the fuel injectors and gasoline detergent additive.
03-06-04-017T2023-08-28. Service bulletin. FUEL SYSTEM, DIESEL. This service bulletin provides information on availability of Diesel Fuel additives.
01-00-89-010R2023-08-28. Service bulletin. EQUIPMENT. This service bulletin provides information on a guide to help reduce repeat visits for the same customer concern.
PIT5909B2023-08-21. Service bulletin. EQUIPMENT:ELECTRICAL. This Preliminary information communicates that it is normal for the tailgate to drop faster than it used to after the GM Accessory Kicker Audio System is installed.
PIP5358C2023-08-21. Service bulletin. EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL. This Preliminary Information communication provides information to the technician about vehicles that have an unusual noise and is difficult to identify, isolate or pinpoint. Technician should get record a sound clip or take a video of the noise for assessment by engineering. Technician will need to call General Motors Technical Assistance Center for further assistance.
PIT5551K2023-08-21. Service bulletin. FORWARD COLLISION AVOIDANCE. This Preliminary information communicates a "Forward Collision System Reduced" message displayed on the DIC when the Forward Automatic Braking has been set to the "Alert" setting. This is normal when the FAB has been set to "Alert".
PIP4902R2023-08-21. Service bulletin. EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL. This Preliminary Information communication provides information to the technician that General Motors Technical Assistance Center may ask for Global Diagnostic System 2 Session Log. Technician will need use Global Diagnostic System 2 to send the session logs to General Motors Technical Assistance Center for further assistance on the vehicle in question.
PIT5990A2023-08-21. Service bulletin. BACK OVER PREVENTION; STRUCTURE. This Preliminary information communicates an issue with a wind noise while driving at highway speeds and dealers are to inspect the body harness pass through for being full seated into the cowl.
PIT5734F2023-08-21. Service bulletin. VISIBILITY:DEFROSTER/DEFOGGER/HVAC SYSTEM. This Preliminary information communicates an issue with poor heater performance and advises dealerships to inspect the heater core inlet and outlet hoses for being twisted or kinked.
22-NA-2322023-08-03. Service bulletin. POWER TRAIN. This informational bulletin advises the technician of a possibly noise coming from the transmission oil pump.
20-NA-0902023-08-03. Service bulletin. ENGINE AND ENGINE COOLING; ELECTRICAL SYSTEM. This informational bulletin provides a way for the technician to identify if the ECM has been modified.
09-06-04-026X2023-08-03. Service bulletin. ELECTRICAL SYSTEM; ENGINE AND ENGINE COOLING. This bulletin provides information on identifying Non-GM Engine Calibrations for Gasoline Engines using the Tech 2 or GDS 2.
03-06-01-023G2023-08-03. Service bulletin. ENGINE AND ENGINE COOLING. This service bulletin explains how to measure for oil consumption and possible reasons for loss of oil.
PIE0701B2023-08-02. Service bulletin. STRUCTURE; EQUIPMENT. This engineering information (EI) closure ends the need to gather further information from technicians regarding taking pictures of decals wrinkling, peeling, bubbling, discoloration, delaminating and/or coming off.
20-NA-1752023-08-02. Service bulletin. STRUCTURE. This technical bulletin provides repair information to correct a customer concern of vertical misalignment between cab and pickup box on driver side of vehicle.
20-NA-1422023-08-02. Service bulletin. POWER TRAIN. This Technical bulletin provides a repair to correct a condition of Shudder/Surging While Driving.
19-NA-2572023-08-02. Service bulletin. STRUCTURE. This technical bulletin provides repair information to correct a customer concern of the pickup box being out of alignment.
19-NA-1292023-08-02. Service bulletin. SUSPENSION. This technical bulletin provides repair information to correct a customer concern of a squeak and/or clunking noise coming from the rear of the vehicle.
N2323953102023-08-02. Service bulletin. ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL; FUEL SYSTEM, GASOLINE. Special Coverage - Certain vehicles may have a condition that could cause the evaporative emissions purge pump to fail. If this condition occurs, the Malfunction Indicator Light (Check Engine Light) will illuminate and a diagnostic trouble code will set. Dealers are to replace the evaporative emissions purge pump as necessary. The repairs will be made at no charge to the customer. The repairs will be made at no charge to the customer.
99-09-40-005I2023-07-28. Service bulletin. SEAT BELTS. This service bulletin provides information on availability for a seat belt extender.
23-NA-0272023-07-26. Service bulletin. FUEL SYSTEM, DIESEL; ENGINE AND ENGINE COOLING; ELECTRICAL SYSTEM. This technical bulletin provides a procedure to test and replace the high-pressure fuel injector electrical connectors if found the cause of the MIL.

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