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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
PIT57422020-05-11. Service bulletin. ENGINE AND ENGINE COOLING. This Preliminary information communicates an issue with the engine wiring harness shorting on the ecm mounting bracket and provides repair instructions.
140604004F2020-04-27. Service bulletin. ENGINE AND ENGINE COOLING. This informational bulletin explains the normal noises an engine may make when the ambient temperature outside is cold or the vehicle has sat for a few hours.
20NA0762020-04-27. Service bulletin. FUEL SYSTEM, GASOLINE; ENGINE. This informational bulletin advises the technician on where to located the fuel injector identification number.
PIT5677C2020-04-13. Service bulletin. ELECTRICAL SYSTEM; ENGINE. This Preliminary information communicates the following issues and directs dealership to inspect the engine harness for shorting. Some customers may comment on any of the following concerns: - SES MIL - No Start - No Crank - Engine runs rough - Reduced engine power - Erratic speedo - Blown Fuse(s): F46UA, F47UA, F51UA, F78UA, F85UA, F86UA, F87UA, and/or F90UA When checking for DTC's any combination may be found: C15AA P001A P2B00 P2B01 P2B03 P2B96 P001B P003D P0107 P018C P01E5 P01E6 P01E7 P0237 P0340 P0341 P0355 P0365 P037C P03F0 P0521 P0522 P0532 P0616 P077C P07BF P1101 P112F P146D P159F p16A0 p16A2 P171B P2122 P26E5 P2812 P2814 P2B53 P2C05 P2C08 P2C09 P2C0C P2C0D P2C10 P2C12 P2C15 P2C16 P2C19 P305E P3084 P3089 P308E P3093 P3094 P3095 P3098 P30B0 P30B3 P30CF U0073 U0100 U0101 U0140 U0644 U0672
PIP5670D2020-04-13. Service bulletin. ENGINE. This preliminary information communicates the part restriction for the diesel turbocharger and EGR components. Updated to provide instruction on gathering additional data.
PIP57122020-04-13. Service bulletin. ENGINE. 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 removal.
PIP57112020-04-13. Service bulletin. ENGINE; ELECTRICAL SYSTEM. This Preliminary information communicates to the dealer technicians a warm engine knock noise has no short or long term effects on the engine. Do not attempt repairs for this noise.
PIE05552020-04-06. Service bulletin. ENGINE. This engineering information (EI) bulletin is requesting information from the field on vehicles experiencing reduced engine power. GM Engineering needs to gather information to root cause the customer concern and develop a field fix.
040601029J2020-04-06. Service bulletin. ENGINE; EQUIPMENT; EQUIPMENT ADAPTIVE/MOBILITY. This informational bulletin explains Unscheduled Supplemental Services (including Flushing Services and Additives) and the Proper use of GM Simplified Maintenance Schedules.
19NA2182020-04-06. Service bulletin. EQUIPMENT; ENGINE. This technical bulletin provides a service procedure to correct a condition of Ticking Noise from the Engine.
20NA0432020-03-30. Service bulletin. ENGINE; EQUIPMENT; EQUIPMENT ADAPTIVE/MOBILITY. This informational bulletin advises the technician to not replace the TMAP sensor, clean it using air or harsh chemicals but allow time for the sensor to thaw.
20NA0392020-03-30. Service bulletin. ENGINE AND ENGINE COOLING:EXHAUST SYSTEM. This technical bulletin provides a procedure to program the ECM and/or replace the exhaust particulate sensor to correct the DTC that set after the service update has been previously performed.
20NA0382020-03-30. Service bulletin. FUEL SYSTEM, DIESEL; ENGINE. This informational bulletin explains the difference in AFM and DFM engines and what is and is not activated during this occurrence.
18NA0732020-03-30. Service bulletin. EQUIPMENT; ENGINE. This 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.
N192266750-022020-03-23. Service bulletin. FUEL SYSTEM, DIESEL; EQUIPMENT; ENGINE AND ENGINE COOLING:COOLING SYSTEM:FAN; ELECTRICAL SYSTEM. Service Update - On vehicles that are equipped with a 6.6L diesel engine, may have one or more of the following conditions exist: 1. The instrument panel cluster may incorrectly display the message ?DEF Low? when a diesel exhaust fluid (DEF) controller internal fault is detected (DTC P20FF), instead of displaying the proper ?Service DEF System? message. 2. The customer may complain of excessive engine fan noise at a low vehicle speed. 3. Under certain conditions, the diagnostic system may set one of the following DTC?s when there is no problem with a component: (P20EE, P226D, P16F3 and P129F). Dealers are to reprogram the engine control module and perform NOx and Catalyst Resets and Regen Enable.
N1922861902020-03-23. Service bulletin. EQUIPMENT; ENGINE AND ENGINE COOLING:ENGINE:DIESEL. Service Update - Certain vehicles may have a condition where the thermal cover may accelerate corrosion of the low pressure diesel hydrocarbon injector. Dealers are to remove the low pressure diesel hydrocarbon injector thermal cover.
N192282970-012020-03-23. Service bulletin. ELECTRICAL SYSTEM; ENGINE. Service Update - Certain vehicles may have a condition where the check engine or the reduced power mode light may come on during start-up or while driving. Reprogram the engine control module and the reductant control module.
PIT57342020-03-09. Service bulletin. ENGINE; VISIBILITY:DEFROSTER/DEFOGGER/HVAC SYSTEM:HEATER CORE. This Preliminary information communicates an issue with poor heater performance and advises dealerships to inspect the heater core inlet and outlet hoses for being twisted or kinked.
PIP5670C2020-03-09. Service bulletin. ENGINE; FUEL SYSTEM, DIESEL. This preliminary information communicates the part restriction for the diesel turbocharger and EGR components. Updated to provide instruction on gathering additional data.
PIP5656D2020-03-09. Service bulletin. EQUIPMENT; ENGINE. This Preliminary Information communication advises the technician that the 6.6L Engine (RPO L8T) has been placed on Engine Exchange program and crankshaft has been placed on part ordering restriction. Dealer will need to contact General Motors Product Quality Center for further assistance.
PIE0549A2020-03-09. Service bulletin. ELECTRICAL SYSTEM; ENGINE. This engineering informational bulletin is requesting information from the field on no crank / no start issue resulting in a starter replacement due to the solenoid overheating.
PIE0515B2020-03-09. Service bulletin. ENGINE; ELECTRICAL SYSTEM. This engineering informational bulletin is requesting information for checking for DTCs and the voltage (relative to a ground) on BOTH sides of the 400A starter fuse in the Battery Distribution Engine Compartment Fuse Block.
19NA2122020-03-02. Service bulletin. ENGINE. This diagnostic tip provides a procedure to aid in performing a diagnostic test to verify if the camshaft alignment pin has been sheared away to correct a crank/No Start condition.
15NA0102020-03-02. Service bulletin. ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL. This informational bulletin provides information to dealership personnel for new vehicles with less than 1,000 miles that may not pass California smog inspection or smog inspection in other states.
PIP5650B2020-02-10. Service bulletin. ENGINE AND ENGINE COOLING. This Preliminary information communicates the possibility of DTC P3075 being set current or history due to low coolant level or air trapped in cooling system.

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