WenmarOpen by Wenmar Pro

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

Bulletins, newest first
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-1832022-10-07. Service bulletin. WHEELS. This informational bulletin advises the tech of a different tire/rim option that can be used to correct the customers concern.
22-NA-1822022-10-07. Service bulletin. POWER TRAIN. This informational bulletin advises the tech to check if the trans cooler lines are twisted which may cause the customers concern.
22-NA-0222022-10-07. Service bulletin. ENGINE AND ENGINE COOLING. 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.
21-NA-1822022-10-07. Service bulletin. EQUIPMENT; ELECTRICAL SYSTEM. This service bulletin provides repair information to correct a customer concern of Radio System Settings Lost or Returning to Default Values.
21-NA-1132022-10-07. Service bulletin. ENGINE AND ENGINE COOLING. This technical bulletin provides a procedure to perform a learn procedure for the turbo actuator.
21-NA-0682022-10-07. Service bulletin. ELECTRICAL SYSTEM; EQUIPMENT. This warranty administration bulletin provides policy information requirements applicable to key fob replacement under the New Vehicle Limited Warranty or under a Replacement Parts Warranty on 2017-2022 and newer model year vehicles with RPO ATH and AVJ.
20-NA-0902022-10-07. Service bulletin. ENGINE AND ENGINE COOLING. This informational bulletin provides a way for the technician to identify if the ECM has been modified.
19-NA-1872022-10-07. Service bulletin. ENGINE AND ENGINE COOLING. This bulletin provides additional information on how to graph a cylinder misfire and a possible diagnostic cause.
18-NA-3612022-10-07. Service bulletin. FUEL SYSTEM, DIESEL. This technical bulletin provides a procedure to flush the cooler lines to validate if there is excessive debris in the fuel system caused by a failed part.
18-NA-1502022-10-07. Service bulletin. ENGINE AND ENGINE COOLING. This informational bulletin provides information on 6.6L Duramax Possible Oil Leak Path Information.
18-NA-0982022-10-07. Service bulletin. ENGINE AND ENGINE COOLING. This informational bulletin provides information for the technicians on where to look on the Duramax engine for coolant leaks.
18-NA-0112022-10-07. Service bulletin. ENGINE AND ENGINE COOLING. Informational bulletin explaining how a plow may cause overheating and engine damage when traveling over 45 mph.
17-NA-3742022-10-07. Service bulletin. ENGINE AND ENGINE COOLING. This informational bulletin advises the technician of how the Soot information has changed from grams to percentage.
16-NA-3762022-10-07. Service bulletin. ENGINE AND ENGINE COOLING. This informational bulletin provides information on higher than expected oil consumption.
16-NA-3722022-10-07. Service bulletin. ENGINE AND ENGINE COOLING. This bulletin provides information on common diesel engine tick noises and how they are considered part of normal operation and no parts should be replaced for these normal operating conditions.
16-NA-2222022-10-07. Service bulletin. ENGINE AND ENGINE COOLING. This bulletin provides information on Engine Concerns that could result from lack of scheduled maintenance, improper service or aftermarket calibrations.
11-00-89-005U2022-10-07. Service bulletin. EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL. This Warranty Administration bulletin provides information on Dealer Empowerment for Goodwill, Customer Enthusiasm and Policy (U.S. Only).
N2123562302022-10-07. Service bulletin. BACK OVER PREVENTION: CAMERA SYSTEM. Certain vehicles may have a condition where the Front Camera Module (FCM) becomes unresponsive and generates a Diagnostic Trouble Code (DTC). Dealers are to re-program the FCM with the latest software available.
N2223750002022-10-03. Service bulletin. VISIBILITY:DEFROSTER/DEFOGGER/HVAC SYSTEM. In certain vehicles, equipped with a manual HVAC system (RPO: C4P), the K33 HVAC Control Module may not properly enable the heater auxiliary coolant pump to maintain cabin heater temperature during engine auto stop events. Reprogram the K33 HVAC Control Module with updated software.
00-06-01-026P2022-09-30. Service bulletin. ENGINE AND ENGINE COOLING. This service bulletin provides information on replacing the intake manifold when the engine is replaced after severe internal engine damage.
PIE0665B2022-09-19. Service bulletin. 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 Service Engine Soon (SES) Lamp illuminated and/or “Service Emissions System” message on the Driver Information Center (DIC).
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.
05-00-89-029E2022-09-19. Service bulletin. EQUIPMENT. This service bulletin provides information on General Motors Dealership Critical Equipment Requirements and Recommendations.

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