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Service bulletins for the 2020 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.

1990 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-1852022-10-13. Service bulletin. POWER TRAIN. This informational bulletin explains how the trans slip or flare can be a normal condition.
15-00-89-004E2022-10-11. Service bulletin. POWER TRAIN; SUSPENSION; ENGINE AND ENGINE COOLING; SERVICE BRAKES, HYDRAULIC; STEERING. 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.
06-00-89-031H2022-10-11. Service bulletin. POWER TRAIN; ENGINE AND ENGINE COOLING. This service bulletin provides information on OEM and Remanufactured Engine and Automatic Transmission/Transaxle Identification.
22-NA-1842022-10-07. Service bulletin. POWER TRAIN. This informational bulletin advises the technician of possibly installing the incorrect 1-2-7-8-R clutch fluid passage seal and which seal should be used with measurements of the seal.
22-NA-1812022-09-19. Service bulletin. POWER TRAIN. This diagnostic tip advises the tech not to separate the flexplate from the torque convertor or damage my occur if the engine is started while diagnosing for noise from the engine or transmission.
22-NA-1762022-09-19. Service bulletin. POWER TRAIN; ENGINE AND ENGINE COOLING. This technical bulletin provides information on a possible bolt and guide pin that may be missing from the control valve which will need to be installed to correct the repair.
21-NA-2752022-09-07. 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.
21-NA-1992022-08-30. 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.
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.
PIP57052022-07-25. Service bulletin. POWER TRAIN; STRUCTURE; AIR BAGS; SUSPENSION. This Preliminary information communicates A vehicle may have a concern of a vibration or drone around 40 MPH and 1200 RPM under a light load. Debris in the tranmission mount. Inspect the transmission mount for debris. If debris is found, clean the mount, reinstall and evaluate for the concern.
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.
21NA2142022-06-21. Service bulletin. POWER TRAIN; POWER TRAIN:AUTOMATIC TRANSMISSION. This technical bulletin provides repair information to correct a customer concern of Service Engine Soon Lamp being illuminated. They may also comment on multiple transmission issues including harsh or delayed shifts, slip, surge, shudder, noise, whine, growl, shake and/or vibration. As well as the exhaust brake not working or that they do not feel it. Technicians may find DTCs P2002, P2463, P2459, P144E, P0421, P0422, P0106 P20EE, P129F, P16F3, P20FF, P226D, P249D, P249E, P11CC and / or P11D5.
21NA2142022-06-21. Service bulletin. POWER TRAIN:AUTOMATIC TRANSMISSION; EQUIPMENT; ENGINE AND ENGINE COOLING. This technical bulletin provides repair information to correct a customer concern of Service Engine Soon Lamp Illuminated, Harsh or Delayed Transmission Shifts Including Slip, Surge, Shudder, Noise, Whine, Growl, Shake and/or Vibration, DTCs P2002, P2463, P2459, P144E, P0421, P0422, P0106 and/or P20EE Set Current or in Recent History.
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.
20-NA-0502022-05-06. Service bulletin. POWER TRAIN. This technical bulletin provides a procedure to clear the codes and test the Tcase if found that the customer has tried to shift the t-case from 4lo to Hi gears while driving.

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