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Service bulletins for the 2018 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.

1723 on file from NHTSA, as of 2026-10-19.

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By component

By trouble code

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

Bulletins, newest first
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-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.
20-NA-1422022-07-01. Service bulletin. POWER TRAIN. This Technical bulletin provides a repair to correct a condition of Shudder/Surging While Driving.
20-NA-1422022-06-02. Service bulletin. POWER TRAIN. This Technical bulletin provides a repair to correct a condition of Shudder/Surging While Driving.
17-NA-0662022-06-01. Service bulletin. POWER TRAIN. This warranty administration bulletin provide policy information for automatic transmission Oil Cooler Flush and flow test.
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.
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.
20-NA-2072022-03-16. Service bulletin. PARKING BRAKE:ELECTRICAL:CONTROL MODULE; ELECTRICAL SYSTEM; POWER TRAIN. This service bulletin informs the technician to inspect for a possible electrical concern at the ECM X2 electrical connector to correct a customer concern of Malfunction Indicator Lamp (MIL) Illuminated - DTC P0333 Set.
PIP5345A2022-02-14. Service bulletin. POWER TRAIN. This Preliminary Information communication provides information to the technician about being to achieve pre-load when setting up the pinion bearing pre-loads during reassembly of the 9.5/9.76 inch rear axles. Technician will need to use pinion gear install washer part number 11609638 onto the pinion shaft between the flange and nut. Tighten the pinion nut until you achieve 10 pound inch or 1.0 newton rotating torque. After the torque has been achieved back the nut off and remove the washer. Tighten the nut back down until you achieve 15 pound inch or 1.7 newton meters for used bearings or 20 pound inch 2.25 newton meters for new bearings.
21NA1992022-02-14. Service bulletin. POWER TRAIN; POWER TRAIN:AUTOMATIC TRANSMISSION:FLUID/LUBRICANT:VALVES/VALVE BODY. 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.
PIP58112022-01-24. Service bulletin. ENGINE AND ENGINE COOLING; POWER TRAIN. This Preliminary information communicates to dealers an issue on remanufactured engines with part numbers 19368174 and 19368176 where the incorrect crankshaft timing gear was installed. Provides dealer with information to correct this condition.
19NA1532021-12-27. Service bulletin. POWER TRAIN; ENGINE AND ENGINE COOLING. This technical bulletin provides a procedure to replace the torque converter and inspect the front pump and the TEHCM for metal.
17NA3452021-12-20. Service bulletin. POWER TRAIN; ELECTRICAL SYSTEM; STEERING. This technical bulletin provides a procedure to reprogram the power steering control module to correct a condition of Loss of Steering Assist due to a software abnormality.
PIC5650J2021-09-13. Service bulletin. POWER TRAIN; AIR BAGS. 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.
990420002L2021-08-09. Service bulletin. POWER TRAIN:MANUAL TRANSMISSION; POWER TRAIN:AUTOMATIC TRANSMISSION; EQUIPMENT. This service bulletin provides information on Driveline Clunk Noise and what is acceptable and what is considered normal operation.
080730035E2021-08-09. Service bulletin. EQUIPMENT; EQUIPMENT ADAPTIVE/MOBILITY; POWER TRAIN. This bulletin provides information on the harmful effects of water or ethylene glycol in transmission fluid.
21NA1132021-07-19. Service bulletin. POWER TRAIN. This technical bulletin provides a procedure to perform a learn procedure for the turbo actuator.
PIP5621B2021-06-14. 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.
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.
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.
174262021-04-30. Service bulletin. EQUIPMENT; POWER TRAIN:MANUAL TRANSMISSION. Condition Certain 2018 model year Chevrolet Silverado and GMC Sierra vehicles, equipped with the manual shift transfer case (RPO NQG), may have a condition in which the transfer case shift linkage rod bolt torque is less than specified. Over time this bolt could loosen enough to allow the transfer case shift indicator to be inaccurate; or the bolt could fall off causing the transfer case to remain in its previous position and the shifter to be non-functional. Correction Tighten the transfer case shift linkage rod bolt to the specified torque
174192021-04-30. Service bulletin. ELECTRICAL SYSTEM:SOFTWARE; POWER TRAIN:AUTOMATIC TRANSMISSION:CONTROL MODULE (TCM/PCM/TECM). Condition Certain 2018 model year Chevrolet Silverado HD and GMC Sierra HD vehicles, equipped with 6.6L diesel engine (RPO L5P) and Allison transmission (RPO MW7), may have a condition in which the automatic transmission has rough upshifts. Correction Reprogram the transmission control module (TCM).
17337-174192021-04-29. Service bulletin. ENGINE AND ENGINE COOLING:ENGINE:ENGINE CONTROL MODULE (ECU/ECM); POWER TRAIN:AUTOMATIC TRANSMISSION:CONTROL MODULE (TCM/PCM/TECM). General Motors released Emission Recall 17337 and Service Update 17419 on November 1, 2017. After their release, a change occurred in Tis2Web that affects the involved 2018 model year Chevrolet Silverado HD and GMC Sierra HD vehicles. This change prevents programming of the engine control module (ECM) and transmission control module (TCM) separately. Tis2Web now requires the ECM and TCM in these full-size trucks to be programmed sequentially. Consequently, dealers are confused and asking for guidance relative to labor code submission requirements. Again, the Tis2Web change only affects the involved 2018 model year Chevrolet Silverado HD and GMC Sierra HD vehicles

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