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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.

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By component

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

Bulletins, newest first
21NA1132021-07-19. Service bulletin. POWER TRAIN. This technical bulletin provides a procedure to perform a learn procedure for the turbo actuator.
21NA1202021-07-06. Service bulletin. POWER TRAIN. This technical bulletin provides the tech with a procedure to check if the transmission is the cause of the concern by checking the data.
PIP58072021-06-14. Service bulletin. POWER TRAIN. This Preliminary information communicates to the dealer technician that it is a normal characteristic for vehicles equipped with the 10L1000 transmission to start off in second gear in normal driving mode. It also communicates that the vehicle will start off in first gear if tow haul is selected.
PIE0615A2021-06-07. Service bulletin. POWER TRAIN; SERVICE BRAKES. This engineering informational bulletin is requesting information from technicians to perform the check list provided and contact the engineer listed in regards on a tick and/or ping type noise heard from the Propeller Shaft during acceleration and/or braking.
20NA2182021-05-24. Service bulletin. POWER TRAIN. This service bulletin provides repair information to correct a customer concern of Possible Crank No Start or Extended Crank with DTC P12A6.
16NA3382021-05-24. Service bulletin. POWER TRAIN. 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.
PIP5794A2021-05-17. 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.
PIP57992021-05-17. Service bulletin. STRUCTURE; POWER TRAIN. This Preliminary information communicates to the dealer technician to replace the transmission valve body on 2019-2021 10 speed transmissions to correct DTCs P2812 and P2814 setting if Service Information does not lead to root case of these DTCs.
PIE06152021-05-03. Service bulletin. POWER TRAIN. This engineering informational bulletin is requesting information from technicians to perform the check list provided and contact the engineer listed in regards on a tick and/or ping type noise heard from the Propeller Shaft during acceleration and/or braking.
20NA1382021-05-03. Service bulletin. ENGINE AND ENGINE COOLING; POWER TRAIN. 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.
PIP5712B2021-04-19. Service bulletin. ENGINE AND ENGINE COOLING:ENGINE:CRANK/CAMSHAFT POSITION SENSOR; POWER TRAIN. This Preliminary information communicates to the technician a service Diagnostic / Repair tip to avoid causing the crankshaft sprocket to disengage from the crankshaft during crankshaft balancer or cam drive system component related service procedures.
PIP57942021-04-19. 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.
PIT5715A2021-04-19. Service bulletin. POWER TRAIN. This Preliminary Information provides information to the technician about a additional diagnostic tip for a check engine lamp for DTC P3055 and P3056 and the start/Stop being inoperative.
PIT5544D2021-04-19. Service bulletin. STEERING; BACK OVER PREVENTION; POWER TRAIN. 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.
PIP5771B2021-04-19. Service bulletin. POWER TRAIN; STRUCTURE. This Preliminary information communicates to the dealer technician to replace the valve body on 8 speed transmissions setting DTC P0796 if no debris is found in the transmission fluid pan. If debris is found in the transmission fluid pan the technician is advised to repair the transmission as needed and replace the valve body.
150089004C2021-03-08. Service bulletin. SUSPENSION:FRONT:MACPHERSON STRUT; SUSPENSION:FRONT:SHOCK ABSORBER; POWER TRAIN:AUTOMATIC TRANSMISSION:FLUID/LUBRICANT. 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.
20NA1422021-03-01. Service bulletin. ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL; POWER TRAIN:AUTOMATIC TRANSMISSION:TORQUE CONVERTER. This Technical bulletin provides a repair to correct a condition of Shudder/Surging While Driving.
16NA0192021-02-22. Service bulletin. POWER TRAIN. This informational bulletin provides information on Transmission Adaptive Functions and Correcting Low Mileage Harsh Shifts, Slips, or Flares.
PIP57702021-02-16. Service bulletin. ELECTRICAL SYSTEM; POWER TRAIN. This Preliminary information communicates to the dealer technician to reprogram the transmission control module after any 10L1000 transmission repair.
PIP57712021-02-16. Service bulletin. STRUCTURE; POWER TRAIN. This Preliminary information communicates to the dealer technician to replace the valve body on the 8L90 transmission setting DTC P0796 if no debris is found in the transmission fluid pan. If debris is found in the transmission fluid pan the technician is advised to repair the transmission as need and replace the valve body.
19NA1362021-02-01. Service bulletin. PARKING BRAKE; EQUIPMENT; POWER TRAIN:TRANSFER CASE (4-WHEEL DRIVE). 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.
16NA0192021-02-01. Service bulletin. POWER TRAIN; ELECTRICAL SYSTEM:SOFTWARE. This informational bulletin provides information on Transmission Adaptive Functions and Correcting Low Mileage Harsh Shifts, Slips, or Flares.
PIP57702021-01-25. Service bulletin. ELECTRICAL SYSTEM; POWER TRAIN. This Preliminary information communicates to the dealer technician to reprogram the transmission control module after any 10L1000 transmission repair.
PIP57712021-01-25. Service bulletin. STRUCTURE; POWER TRAIN. This Preliminary information communicates to the dealer technician to replace the valve body on the 8L90 transmission setting DTC P0796 if no debris is found in the transmission fluid pan. If debris is found in the transmission fluid pan the technician is advised to repair the transmission as need and replace the valve body.
PIE0583B2020-12-21. Service bulletin. POWER TRAIN. This engineering information (EI) is requesting information from technicians and to contact the engineers listed in regards to Transmission Performance Issues without a Current or History DTC and Unable to Duplicate the Customer Concern (CCND).

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