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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

Only bulletins with component: Fuel system are shown. Show all

Bulletins, newest first
PIE06952022-06-01. Service bulletin. FUEL SYSTEM, DIESEL; 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 Service Emission System and/or DEF Level Low message on driver information center (DIC).
18NA3612022-05-31. Service bulletin. FUEL SYSTEM, GASOLINE. 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.
18NA2352022-05-31. Service bulletin. FUEL SYSTEM, OTHER:DELIVERY:FUEL PUMP. This information bulletin advised the tech of possible use of low fuel quality and the possible ramifications in performance in regards to the customers concerns.
18NA1032022-05-31. Service bulletin. EXTERIOR LIGHTING; FUEL SYSTEM, GASOLINE. This service bulletin provides service information for customer concerns of an in-tank fuel pump whining noise, engine hard to start and/or stalls and Malfunction Indicator Lamp (MIL) is illuminated that may be caused by gelling of fuel in cold temperatures.
16NA3722022-05-31. Service bulletin. FUEL SYSTEM, DIESEL; FUEL SYSTEM, GASOLINE. 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.
16NA2442022-05-31. Service bulletin. FUEL SYSTEM, DIESEL; FUEL SYSTEM, GASOLINE. This informational bulletin provides information on Diesel Exhaust Fluid (DEF) and the proper use of the DEF system.
22-NA-0872022-05-18. Service bulletin. FUEL SYSTEM, GASOLINE:FUEL INJECTION SYSTEM:INJECTORS; ENGINE. This technical bulletin provides a procedure to replace the fuel injector and the wiring harness to correct a customer concern of Malfunction Indicator Lamp (MIL) Illuminated with DTC P0201, P0202, P0203, P0204, P0205, P0206 and/or P0216 Set.
04-06-04-051F2022-04-05. Service bulletin. FUEL SYSTEM, GASOLINE:FUEL INJECTION SYSTEM; EQUIPMENT:MECHANICAL. This service bulletin provides information for maintenance cleaning of the fuel injectors and gasoline detergent additive.
PIP58382022-03-14. Service bulletin. FUEL SYSTEM, DIESEL; FUEL SYSTEM, GASOLINE; ELECTRICAL SYSTEM. This Preliminary information communicates to the dealership technician a change made to the wire harness and reductant control module for the Diesel Exhaust Fluid tank connector.
PIT5732B2022-03-14. Service bulletin. FUEL SYSTEM, GASOLINE. This Preliminary information provides information to the technician on relocating the DEF tank to install a service body. Technician will need to reference the latest version of General Motors Up-fitter Integration Bulletin 156. The information can be found at http://www.gmupfitter.com/ under the "Technical Bulletin" Tab and then "Show all bulletins."
PIP4723F2022-02-14. Service bulletin. SERVICE BRAKES, HYDRAULIC; FUEL SYSTEM, GASOLINE. This Preliminary Information communicates to the dealer the process for downloading or updating operating software for the Tire Pressure Monitor, Active Fuel Injector tester, multi media tester, PICO Scope, GR8 starting/charging tester and Vehicle Data Recorder tools, giving website address and step by step instructions to complete the update.
N212342980-012022-02-04. Service bulletin. ENGINE AND ENGINE COOLING:ENGINE:DIESEL; ELECTRICAL SYSTEM:SOFTWARE; FUEL SYSTEM, DIESEL. Service Update. On certain vehicles equipped with a 6.6L diesel engine (RPO L5P), the DEF tank connector may overheat and set the following diagnostic codes (P10D9, P143C and P10F3), which will result in reduced engine speed. Dealers are to reprogram the reductant control module.
N2123429802022-01-27. Service bulletin. ELECTRICAL SYSTEM; FUEL SYSTEM, DIESEL. On certain vehicles equipped with a 6.6L diesel engine (RPO L5P), the DEF tank connector may overheat and set the following diagnostic codes (P10D9, P143C and P10F3), which will result in reduced engine speed. Dealers are to reprogram the reductant control module.
20NA1102021-12-20. Service bulletin. FUEL SYSTEM, GASOLINE. This service bulletin advises the technician on what to do if the DEF pump has been replaced and perform a leak test to prime the pump.
PIP5792B2021-09-13. Service bulletin. FUEL SYSTEM, GASOLINE; POWER TRAIN. This Preliminary information communicates to the dealer technician that if a customer comments that their vehicle equipped with a 6L80, 6L90, 8L90, 10L80, or 10L1000 transmission has a harsh shift, shudder, stall or high transmission fluid temperature concern they should inspect for a twisted transmission cooler line. Technicians are instructed to disconnect the cooler line and untwist it then reconnect the cooler line and inspect the cooler line for being misshaped. Technicians are instructed to replace the cooler line if it is misshaped.
N2123365702021-08-09. Service bulletin. ELECTRICAL SYSTEM; ENGINE AND ENGINE COOLING:ENGINE:ENGINE CONTROL MODULE (ECU/ECM); FUEL SYSTEM, GASOLINE. Service Update. Certain trucks may falsely set fuel injector diagnostic trouble codes P026C and/or P20EE. Dealers will reprogram the engine control module (ECM).
21NA1242021-07-19. Service bulletin. FUEL SYSTEM, GASOLINE:STORAGE:EVAPORATIVE EMISSIONS:CANISTER. This service bulletin provides diagnostic tips/steps on testing for possible EVAP leaks in the system to correct a customer concern of an MIL Illuminated with DTCs P0442 and/or P0455 Set.
18NA3612021-07-19. Service bulletin. FUEL SYSTEM, DIESEL; ELECTRICAL SYSTEM. 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.
18NA3612021-07-06. Service bulletin. FUEL SYSTEM, GASOLINE. 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.
PIP5792A2021-06-14. Service bulletin. POWER TRAIN; FUEL SYSTEM, GASOLINE. This Preliminary information communicates to the dealer technician that if a customer comments that their vehicle equipped with a 6L80, 6L90, 8L90, 10L80, or 10L1000 transmission has a harsh shift, shudder or stall concern they should inspect for a twisted transmission cooler line. Technicians are instructed to disconnect the cooler line and untwist it then reconnect the cooler line and inspect the cooler line for being misshaped. Technicians are instructed to replace the cooler line if it is misshaped.
20NA1972021-05-03. Service bulletin. FUEL SYSTEM, GASOLINE. This technical bulletin provides a procedure to inspect and repair the fuel pressure sensor if found the cause of the customers concern.
PIP57922021-04-19. Service bulletin. FUEL SYSTEM, GASOLINE; POWER TRAIN. This Preliminary information communicates to the dealer technician that if a customer comments that their vehicle equipped with a 6L80, 6L90, 8L90, 10L80, or 10L1000 transmission has a harsh shift, shudder or stall concern they should inspect for a twisted transmission cooler line. Technicians are instructed to disconnect the cooler line and untwist it then reconnect the cooler line and inspect the cooler line for being misshaped. Technicians are instructed to replace the cooler line if it is misshaped.
21NA0022021-03-01. Service bulletin. EQUIPMENT:ELECTRICAL:ENGINE BLOCK HEATER; ENGINE AND ENGINE COOLING:ENGINE:ENGINE CONTROL MODULE (ECU/ECM); FUEL SYSTEM, DIESEL. This informational bulletin provides a test procedure, for a possible faulty DEF Heater.
20NA1102021-03-01. Service bulletin. FUEL SYSTEM, DIESEL; EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL; EQUIPMENT. This informational bulletin advises the technician on what to do if the DEF pump has been replaced and perform a leak test to prime the pump.
18NA2852021-03-01. Service bulletin. EQUIPMENT; FUEL SYSTEM, OTHER:KINETIC:CLUTCH. This informational bulletin advises the tech of a possible normal condition when the vehicle creeps forward during start up conditions when the clutch packs are full of residual oil.

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