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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
PIT59292022-08-15. Service bulletin. POWER TRAIN. This Preliminary information communicates an issue with the power assist steps having erratic operation and not staying deployed. Engineering is working on a fix.
21-NA-1992022-08-04. Service bulletin. POWER TRAIN. This informational bulletin advises the technician to replace the TBV if the transmission has any type of repair even if no problem was found, to replace the tbv.
22-NA-0152022-08-03. Service bulletin. FUEL SYSTEM, OTHER:FUEL INJECTION SYSTEM; ENGINE AND ENGINE COOLING; POWER TRAIN. 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.
PIP5792D2022-07-25. Service bulletin. POWER TRAIN; FUEL SYSTEM, GASOLINE. This Preliminary information communicates to the dealer technician that if a customer comments that their vehicle equipped with a 6L80, 6L90, 8L90, 10L80, or 10L1000 transmission has a harsh shift, shudder, stall or high transmission fluid temperature concern they should inspect for a twisted transmission cooler line. Technicians are instructed to disconnect the cooler line and untwist it then reconnect the cooler line and inspect the cooler line for being misshaped. Technicians are instructed to replace the cooler line if it is misshaped.
20-NA-1422022-07-01. Service bulletin. POWER TRAIN. This Technical bulletin provides a repair to correct a condition of Shudder/Surging While Driving.
22NA0222022-06-21. Service bulletin. POWER TRAIN:AUTOMATIC TRANSMISSION:FLUID/LUBRICANT:SEALS/GASKETS. This Informational bulletin advises the technician of a possible oil leak at the front cover and how to diagnose it to verify if it is coming from the seal or not.
21NA2382022-06-21. Service bulletin. POWER TRAIN; FUEL SYSTEM, GASOLINE. This technical bulletin provides a procedure to inspect the front pump of the transmission for a possible leak.
PIE06762022-06-13. Service bulletin. POWER TRAIN; ENGINE AND ENGINE COOLING. This engineering information (EI) is requesting information from technicians to perform the check list provided and contact the engineer listed in regards to Engine Coolant Reservoir Being Overfilled with Discolored Coolant, Shudder, Shake, Vibration, Harsh Shift, Delayed Shift and/or Slipping Transmission Performance.
PIE0665A2022-06-10. Service bulletin. ENGINE AND ENGINE COOLING:EXHAUST SYSTEM; ELECTRICAL SYSTEM; POWER TRAIN. This engineering informational bulletin is requesting information from technicians to perform the check list provided and contact the engineer listed in regards to Service Engine Soon (SES) Lamp illuminated and/or “Service Emissions System” message on the Driver Information Center (DIC).
21-NA-2752022-06-04. 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.
20-NA-1422022-06-02. Service bulletin. POWER TRAIN. This Technical bulletin provides a repair to correct a condition of Shudder/Surging While Driving.
2-NA-0662022-05-31. Service bulletin. POWER TRAIN. The technical bulletin provides a procedure to lube the yoke and caps if found the cause of the noise from the propshaft area.
16NA3612022-05-31. Service bulletin. AIR BAGS; 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.
PIP5794B2022-05-16. Service bulletin. POWER TRAIN. This Preliminary information communicates diagnostics to the dealer involving a vehicle shudder concern caused by the camshaft actuator system that can be mistaken for a transmission issue.
16-NA-0192022-05-10. Service bulletin. POWER TRAIN. This service bulletin provides information on Transmission Adaptive Functions and Correcting Low Mileage Harsh Shifts, Slips, or Flares.
PIP58452022-04-18. Service bulletin. POWER TRAIN; ENGINE AND ENGINE COOLING. This Preliminary information communicates to the dealer technician that if the vehicle's engine coolant reservoir has transmission fluid in it or if Glycol it found in the transmission fluid the dealer should replace the Automatic Transmission Fluid Cooling Exchanger. The dealer should refer to bulletin 08-07-30-035 for the recommended components that should be replaced in the transmission and to flush the engine cooling system following service information.
PIP5706A2022-04-18. Service bulletin. POWER TRAIN. This Preliminary information communicates to the dealer a condition with the throttle body that may illuminate the service engine soon light, cause the engine to run rough and/or display reduced engine power message. Dealers are instructed to replace the throttle body assembly and install a grounding wire from the throttle body to the valve cover to prevent future failures.
PIE0676A2022-04-06. Service bulletin. POWER TRAIN; ENGINE AND ENGINE COOLING. This engineering information (EI) closure ends the need for further information from the field in regards to Engine Coolant Reservoir Being Overfilled with Discolored Coolant, Shudder, Shake, Vibration, Harsh Shift, Delayed Shift and/or Slipping Transmission Performance.
22-NA-0662022-04-06. Service bulletin. POWER TRAIN. The technical bulletin provides a procedure to lube the yoke and caps if found the cause of the noise from the propshaft area.
22-NA-0152022-04-05. Service bulletin. ENGINE AND ENGINE COOLING; POWER TRAIN. 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.
20-NA-2092022-04-05. Service bulletin. ELECTRICAL SYSTEM; POWER TRAIN. This technical bulletin provides repair information to correct a customer concern of Service 4WD Message illuminated on Driver Information Center (DIC), DTCs C118D, C119B and/or C119C set.
21-NA-0952022-03-18. Service bulletin. POWER TRAIN. This technical bulletin provides a procedure to seal the exhaust at the UFSCR and Tailpipe flange.
PIP5653M2022-03-14. Service bulletin. POWER TRAIN:AXLE ASSEMBLY. This Preliminary information communicates that engineering is investigating a repair for a chirp noise associated with the front axle assembly.
PIP58342022-03-14. Service bulletin. UNKNOWN OR OTHER; POWER TRAIN:AUTOMATIC TRANSMISSION. This Preliminary information communicates that the service 4wd message related to C119E is under investigation for a repair.
PIP57952022-03-14. Service bulletin. POWER TRAIN:AUTOMATIC TRANSMISSION. This Preliminary information communicates to technicians to replace the rear cover with seal in the event of a rear oil seal leak.

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