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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: Engine are shown. Show all

Bulletins, newest first
PIE0590A2021-03-08. Service bulletin. ENGINE; EQUIPMENT; ELECTRICAL SYSTEM:INTERIOR LAMPS/BULBS. This engineering informational bulletin is requesting information from technicians to perform the check list provided and contact the engineer listed in regards check to the engine lamp being illuminated on the drivers information center (DIC).
21NA0072021-03-01. Service bulletin. ELECTRICAL SYSTEM; ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL. This technical bulletin provides a procedure to program the reductant fluid module if found the cause of the customers concern.
21NA0062021-03-01. Service bulletin. ELECTRICAL SYSTEM; ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL. This bulletin provides a possible location of a bad connection at the reductant fluid tanks electrical connector.
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.
20NA2182021-03-01. Service bulletin. EQUIPMENT; ENGINE AND ENGINE COOLING:ENGINE:ENGINE CONTROL MODULE (ECU/ECM):SOFTWARE. This technical bulletin provides repair information to correct a customer concern of Possible Crank No Start or Extended Crank with DTC P12A6.
20NA2032021-03-01. Service bulletin. EQUIPMENT ADAPTIVE/MOBILITY; EQUIPMENT; ENGINE AND ENGINE COOLING:EXHAUST SYSTEM. This informational bulletin explains how the regen works for the DEF system and how it works at different levels.
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.
18NA0732021-03-01. Service bulletin. ENGINE. This service bulletin provides graphics, information and guidelines for engine component wear to assist service personnel as a guideline to perform necessary engine repairs and prevent unnecessary engine replacement.
PIE0601A2021-03-01. Service bulletin. ENGINE; ELECTRICAL SYSTEM. This engineering informational bulletin is requesting information from technicians to perform the check list provided and contact the engineer listed in regards to the Service Engine Soon Lamp being illuminated.
PIE0578C2021-03-01. Service bulletin. ELECTRICAL SYSTEM; ENGINE. This engineering informational bulletin is requesting information from technicians to perform the check list provided and contact the engineer listed in regards to a Slow Start and/or No Start, Battery Message Indicated, having to jump start on more then one occasion.
090604026S2021-03-01. Service bulletin. ENGINE AND ENGINE COOLING:ENGINE:GASOLINE; EQUIPMENT. This bulletin provides information on identifying Non-GM Engine Calibrations for Gasoline Engines using the Tech 2 or GDS 2.
010601011L2021-03-01. Service bulletin. ENGINE AND ENGINE COOLING:ENGINE:OIL/LUBRICATION; EQUIPMENT. This informational bulletin provides guidelines and diagnostic/repair information to technicians regarding vehicle engine oil consumption.
N202319660 012021-03-01. Service bulletin. EQUIPMENT ADAPTIVE/MOBILITY; EQUIPMENT; ENGINE AND ENGINE COOLING:ENGINE:HARD PARTS INTERNAL/MECHANICAL. Service Update. Certain vehicles may present a broken engine valve spring. This may cause the engine to run rough, an engine knocking or ticking noise, a check engine light illumination, or a possible vehicle stall. Dealers are to perform the inspection procedure contained within this bulletin.
20NA2182021-02-22. Service bulletin. ENGINE AND ENGINE COOLING:ENGINE:ENGINE CONTROL MODULE (ECU/ECM):SOFTWARE; EQUIPMENT. This technical bulletin provides repair information to correct a customer concern of Possible Crank No Start or Extended Crank with DTC P12A6.
19NA2182021-02-22. Service bulletin. ENGINE AND ENGINE COOLING. This technical bulletin provides a service procedure to correct a condition of Ticking Noise from the Engine.
19NA1362021-02-22. Service bulletin. ENGINE AND ENGINE COOLING. 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.
17NA1662021-02-22. Service bulletin. ENGINE AND ENGINE COOLING. This technical bulletin provides a procedure to measure vibration and install engine mounts to correct a Rough Idle in Drive concern.
N202319660 012021-02-22. Service bulletin. ENGINE AND ENGINE COOLING. Service Update. Certain vehicles may present a broken engine valve spring. This may cause the engine to run rough, an engine knocking or ticking noise, a check engine light illumination, or a possible vehicle stall. Dealers are to perform the inspection procedure contained within this bulletin.
N202319660 012021-02-16. Service bulletin. ENGINE; EQUIPMENT. Service Update. Certain vehicles may present a broken engine valve spring. This may cause the engine to run rough, an engine knocking or ticking noise, a check engine light illumination, or a possible vehicle stall. Dealers are to perform the inspection procedure contained within this bulletin.
PIT5479D2021-02-16. Service bulletin. ENGINE AND ENGINE COOLING. This Preliminary Information communication provides information to the technician about fluid leaking from the brake caliper piston area found during a service of the vehicle. The substance is actually excess assembly grease from the caliper boot and piston installation. This grease can be cleaned off and the rest of the service completed.
PIE0601A2021-02-01. Service bulletin. ELECTRICAL SYSTEM; ENGINE. This engineering informational bulletin is requesting information from technicians to perform the check list provided and contact the engineer listed in regards to the Service Engine Soon Lamp being illuminated.
PIE0578C2021-02-01. Service bulletin. EQUIPMENT; ELECTRICAL SYSTEM; EQUIPMENT ADAPTIVE/MOBILITY; ENGINE. This engineering informational bulletin is requesting information from technicians to perform the check list provided and contact the engineer listed in regards to a Slow Start and/or No Start, Battery Message Indicated, having to jump start on more then one occasion.
090604026S2021-02-01. Service bulletin. EQUIPMENT; EQUIPMENT ADAPTIVE/MOBILITY; ENGINE AND ENGINE COOLING. This bulletin provides information on identifying Non-GM Engine Calibrations for Gasoline Engines using the Tech 2 or GDS 2.
010601011L2021-02-01. Service bulletin. ENGINE AND ENGINE COOLING; EQUIPMENT. This informational bulletin provides guidelines and diagnostic/repair information to technicians regarding vehicle engine oil consumption.
20NA2182021-02-01. Service bulletin. ENGINE AND ENGINE COOLING:ENGINE:ENGINE CONTROL MODULE (ECU/ECM):SOFTWARE; ENGINE AND ENGINE COOLING. This technical bulletin provides repair information to correct a customer concern of Possible Crank No Start or Extended Crank with DTC P12A6.

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