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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

Only bulletins with component: Transmission and driveline are shown. Show all

Bulletins, newest first
22-NA-2512023-11-22. Service bulletin. EQUIPMENT; POWER TRAIN. This service bulletin provides a procedure to replace the front wheel drive shaft to correct a customer concern of a Squeak/Chirp Noise from Front Axle in 2wd.
03-00-91-001I2023-11-22. Service bulletin. WHEELS; POWER TRAIN; STEERING; SUSPENSION; ENGINE AND ENGINE COOLING. This service bulletin provides a vibration analysis worksheet the technician can use in conjunction with the appropriate Vibration Analysis-Road testing procedure when diagnosing vibration concerns.
23-NA-1852023-11-15. Service bulletin. POWER TRAIN; EQUIPMENT; ELECTRICAL SYSTEM; STEERING. This service bulletin helps diagnose/reduce possible CCND issues on Transfer Cases - Service 4WD on DIC, Intermittent Failures, Noise Concerns, Driveline/Steering Vibration/Shudder, Intermittent DTCs/MIL Illuminated, Engagement/Disengagement/Ratcheting Concerns.
22-NA-2252023-11-10. Service bulletin. POWER TRAIN; EQUIPMENT. This information bulletin advises the technician the difference between a welch cap leak and the output seal of the t-case or transmission leaking ATF, causing the customer concern of a Red Fluid Leak from Center of Vehicle Located by Rear of Transmission or Transfer Case Area.
16-NA-3612023-11-10. Service bulletin. POWER TRAIN. This service bulletin provides service /diagnostic information to aid with a Transmission Harsh 1-2 Shift Upon First Start Up/Shift of the Day Under Light Throttle.
21-NA-2752023-11-06. Service bulletin. POWER TRAIN. This service bulletin provides repair information to correct customer concerns of Rear Wheel Lock Up, ABS Event, Loud Bang and a Flashing “D” on Driver Information Center (DIC) when Lightly or Moderately Accelerating Forcing an 8-7 or 8-6 Downshift.
22-NA-0152023-10-14. Service bulletin. POWER TRAIN; ENGINE AND ENGINE COOLING. This informational bulletin provides graphs to help identify possible issues that may cause shaking and shudders and what may be the cause of said issue.
21-NA-1202023-10-14. Service bulletin. POWER TRAIN; EQUIPMENT. This service bulletin provides a Diagnostic Tip for Noise, Vibration, and/or Harshness Issues/Clunk Noise Heard During Coast Down Event after the transfer case was removed from the transmission and reinstalled during a recent repair.
20-NA-1422023-10-10. Service bulletin. POWER TRAIN. This Technical bulletin provides a repair to correct a condition of Shudder/Surging While Driving.
23-NA-1532023-09-26. Service bulletin. ENGINE AND ENGINE COOLING; POWER TRAIN. The service bulletin advises the tech of a normal transmission shift condition and the delay in throttle response when the throttle plate is opened rapidly and advises the customer that it is normal for the delay.
PIP5621D2023-09-18. Service bulletin. POWER TRAIN. This Preliminary information communicates to the dealer technician that TAC recommends the utilization of the GDS2 software to aid in diagnosing automatic transmission concerns. TAC is requesting the GDS2 session logs be sent in before the dealer contacts TAC.
22-NA-1872023-09-15. Service bulletin. POWER TRAIN; ELECTRICAL SYSTEM. This informational bulletin advises the tech to inspect the transfer case motor electrical connectors for possible damage or corrosion that might be caused by a damage grommet inside the electrical connector.
22-NA-1822023-09-13. 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.
15-00-89-004F2023-09-08. Service bulletin. STEERING; SUSPENSION; ENGINE AND ENGINE COOLING; POWER TRAIN. This service bulletin provides technicians with updated information to help identify the differences between what is considered a fluid leak, and what is considered fluid seepage.
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-1422023-08-02. Service bulletin. POWER TRAIN. This Technical bulletin provides a repair to correct a condition of Shudder/Surging While Driving.
17-NA-0662023-07-25. Service bulletin. POWER TRAIN:AUTOMATIC TRANSMISSION; POWER TRAIN. This service bulletin provides information for automatic transmission Oil Cooler Flush and flow test.
PIP5926B2023-07-17. Service bulletin. POWER TRAIN. This Preliminary information communicates that the t-case input seal, and/or the o-ring most likely is the source of the leak between the transmission and the t-case.
PIP5926A2023-07-17. Service bulletin. POWER TRAIN:AUTOMATIC TRANSMISSION:FLUID/LUBRICANT. This Preliminary information communicates that the t-case input seal, and/or the o-ring most likely is the source of the leak between the transmission and the t-case.
PIP59262023-07-17. Service bulletin. POWER TRAIN. This Preliminary information communicates that the t-case input seal, and/or the o-ring most likely is the source of the leak between the transmission and the t-case.
17-NA-0662023-07-13. Service bulletin. POWER TRAIN. This service bulletin provides information for automatic transmission Oil Cooler Flush and flow test.
22-NA-2322023-07-11. Service bulletin. POWER TRAIN; ENGINE AND ENGINE COOLING; ENGINE AND ENGINE COOLING:ENGINE:OIL/LUBRICATION:PUMP. This informational bulletin advises the technician of a possibly noise coming from the transmission oil pump.
04-07-30-013E2023-06-19. Service bulletin. POWER TRAIN; ENGINE AND ENGINE COOLING. This service bulletin provides information to dealership personnel on automatic transmission shift and engine driveability concerns and/or MIL ON due to aftermarket oil bath air filter use.
PIT5544G2023-06-13. Service bulletin. BACK OVER PREVENTION; POWER TRAIN; STEERING. This Preliminary information communicates information on a hydrauilc rush type noise from the power steering gear. This noise is a characteristic of the new Active Hydraulic Assist System RPO NV8 and no repairs should be made. The noise is most noticeable in the cab at idle, in park, with all accessories turned off.
PIC5650K2023-06-13. Service bulletin. POWER TRAIN; ELECTRICAL SYSTEM:IGNITION. 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, and/or B3935. Technician should not replace any parts for this concern. If unable to duplicate the concern ask if the customer uses any Radio Frequency Identification Devices when the concern is present. Dealer should also direct their customers to the appropriate section in the Owner manuals that references that the device complies.

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