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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
PIP59002023-03-13. Service bulletin. POWER TRAIN. This Preliminary information communicates to the dealer a diagnostic and repair direction to a possible engine crankshaft bearing failure.
16-NA-1302023-03-08. Service bulletin. POWER TRAIN; POWER TRAIN:AUTOMATIC TRANSMISSION:FLUID/LUBRICANT:VALVES/VALVE BODY. This service bulletin provides information for after installation of a replacement upper valve body, the transmission may have no Reverse and no 2nd gear.
99-04-20-002N2023-03-03. Service bulletin. POWER TRAIN. This service bulletin provides information on Driveline Clunk Noise and what is acceptable and what is considered normal operation.
22-NA-0152023-02-08. 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.
22-NA-2322023-02-08. Service bulletin. POWER TRAIN. This informational bulletin advises the technician of a possibly noise coming from the transmission oil pump.
22-NA-1872023-02-07. Service bulletin. ELECTRICAL SYSTEM; POWER TRAIN. 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.
21-NA-2382023-02-07. Service bulletin. POWER TRAIN. This technical bulletin provides a procedure to inspect the front pump of the transmission for a possible leak.
20-NA-1872023-01-25. Service bulletin. POWER TRAIN. This service bulletin provides a repair procedure to correct a customer concern of Delayed and/or Harsh Engagement of Transmission Shift After Vehicle Sitting with Engine Off.
20-NA-1422023-01-25. Service bulletin. POWER TRAIN. This Technical bulletin provides a repair to correct a condition of Shudder/Surging While Driving.
22-NA-2512023-01-25. Service bulletin. POWER TRAIN; WHEELS. This technical bulletin provides a procedure to replace the front wheel drive shaft if found the cause of the custmers concern.
19-NA-1362023-01-06. Service bulletin. POWER TRAIN. This service bulletin provides a diagnostic procedure to aid in correcting a customer concern of a Howling, Whining/Whirring Noise, Shudder/Vibration and/or Grinding Noise While in 4HI, 4HI Auto and/or During Parking Lot Maneuvers in Auto Mode.
16-NA-3382023-01-05. Service bulletin. POWER TRAIN; ENGINE AND ENGINE COOLING. This Warranty Admin service bulletin provides guidelines for Dealers Not Required and for Dealers Required to Contact the PQC for engine or transmission assembly replacement and explains the PQC process, GWM Transaction submission, vehicle service record retention and proper handling of assembly returns for Canadian Dealers only.
22-NA-2462022-12-23. Service bulletin. POWER TRAIN. This service bulletin advises the technician that the possible cause may not be from a faulty clutch piston or extension housing and to perform testing on transmission for possible other issues, but it still may be possible on high mile vehicles that orifices in housing may have come dislodged, causing the same customer concern.
20-NA-1422022-12-07. Service bulletin. POWER TRAIN. This Technical bulletin provides a repair to correct a condition of Shudder/Surging While Driving.
22-NA-2322022-12-06. Service bulletin. POWER TRAIN. This informational bulletin advises the technician of a possibly noise coming from the transmission oil pump.
21-NA-1202022-12-06. Service bulletin. POWER TRAIN. 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-1382022-12-06. Service bulletin. POWER TRAIN; ENGINE AND ENGINE COOLING. This bulletin provides information on Policies Applicable to All U.S. Dealers for Engine and Transmission Assembly Replacement Under Warranty, Policy or Customer Enthusiasm and information on Submission of Warranty Transaction in Global Warranty Management.
19-NA-1362022-12-06. Service bulletin. POWER TRAIN. This service bulletin provides a diagnostic procedure to aid in correcting a customer concern of a Howling, Whining/Whirring Noise, Shudder/Vibration and/or Grinding Noise While in 4HI, 4HI Auto and/or During Parking Lot Maneuvers in Auto Mode.
22-NA-2252022-12-03. Service bulletin. POWER TRAIN. This information advises the technician the difference between a welch cap leak and the output seal of the t-case or transmission leaking ATF causing the customers concern.
PIP5175E2022-11-21. Service bulletin. POWER TRAIN; ENGINE AND ENGINE COOLING. This Preliminary Information communication provides information to the technician about vehicles that may have a delayed engagement into drive, shudder at a launch, or the transmission is slipping when shifting into 1st, 2nd, 3rd or 4th gears. This may be due to loose stator support to pump cover bolts causing a leak at the stator support to pump cover gasket. Technician will check for the bolts to be loose. If any of the bolts are loose or the gasket is misaligned or leaking, the transmission pump cover must be replaced and the 1234 clutch plates should be inspected for being distressed and repaired as needed.
PIP58822022-11-21. Service bulletin. POWER TRAIN. This Preliminary information communicates diagnostic aid to help isolate possible repeat thermal by-pass valve concern.
PIP5429A2022-10-17. Service bulletin. ELECTRICAL SYSTEM; POWER TRAIN. This Preliminary Information communication advises the technician that the customer may experience a 2-3 slip or flare after the vehicle has been sitting for a period of time. Technician can update the Transmission Control Module if working on a model year 2007. On all other model years dealer should communicate to the customer this condition is a normal operating characteristic of their vehicle.
PIP5810A2022-10-17. Service bulletin. POWER TRAIN:TRANSFER CASE (4-WHEEL DRIVE). This Preliminary information communicates that the tool for the HD transfer cases to install the input seal during a repair is incorrect and a new tool is in development.
PIP5621C2022-10-17. Service bulletin. POWER TRAIN:AUTOMATIC TRANSMISSION:CONTROL MODULE (TCM/PCM/TECM); 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.
PIP5640A2022-10-17. Service bulletin. POWER TRAIN. This Preliminary Information communication provides information to the technician to not remove the torque converter bolts and start the engine as this may cause damage to the torque converter of the crankshaft on vehicles equipped with an automatic transmission.

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