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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

Bulletins, newest first
040089015U2020-04-06. Service bulletin. EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL. This bulletin provides information on Warranty Administration ? Required Operating Procedures - 8 Points (U.S. Only).
000310003Y2020-04-06. Service bulletin. EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL; TIRES. This warranty administration bulletin provides information on the tires supplied with a new vehicle are covered by General Motors against defects in material or workmanship under the Bumper-to-Bumper New Vehicle Limited Warranty.
20NA0192020-04-06. Service bulletin. POWER TRAIN. This technical bulletin provides a procedure to replace the transmission shifter control if found the cause of the condition.
20NA0062020-04-06. Service bulletin. EQUIPMENT ADAPTIVE/MOBILITY; EQUIPMENT; STEERING. This informational bulletin explains there is another steering hose that can be used for cold weather drivers that experience a steering hose leak.
19NA2182020-04-06. Service bulletin. EQUIPMENT; ENGINE. This technical bulletin provides a service procedure to correct a condition of Ticking Noise from the Engine.
19NA1042020-04-06. Service bulletin. EQUIPMENT; STRUCTURE:BODY; EQUIPMENT ADAPTIVE/MOBILITY. This informational bulletin provides information for dealers/technicians and customers on steam/vapor coming from the front grille or radiator area.
18NA3832020-04-06. Service bulletin. STRUCTURE. This technical bulletin provides repair information to correct a customer concern of water found in rear interior of cab due to water leak at rear sliding window.
DOR-D8C4T-032020-03-30. Service bulletin. ELECTRICAL SYSTEM; VISIBILITY:POWER WINDOW DEVICES AND CONTROLS. This SKU is a Power Window Regulator and Motor Assembly. The customer communication requested return of unsold inventory to inspect the software. The software may be too sensitive to the position of a locating magnet in the assembly causing the activation of the pinch point threshold prematurely. The window will stay open when it should have closed.
20NA0442020-03-30. Service bulletin. EQUIPMENT. This technical bulletin provides repair information to correct a customer concern of endgate will not auto open or auto close after accessory tonneau cover installation, and/or poor fit of tonneau cover to endgate.
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.
20NA0402020-03-30. Service bulletin. EQUIPMENT ADAPTIVE/MOBILITY; LATCHES/LOCKS/LINKAGES:TAILGATE:LATCH. This technical bulletin provides repair information to correct a customer concern of the pickup box power endgate may not open on initial press, or may not open at all.
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.
16NA1192020-03-30. Service bulletin. EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL. This warranty administration bulletin provide policy information to cover GMs policy on performing GM covered vehicle services and maintenance on vehicles originating/sold in Canada.
N2022948202020-03-23. Service bulletin. SERVICE BRAKES; ELECTRICAL SYSTEM. Customer Satisfaction Program - The brake system control module software in these vehicles may contain an error. If (i) the vehicle is started remotely using the MyChevrolet, MyGMC, or MyCadillac mobile app or (ii) the driver enters the vehicle and waits five or more minutes before starting the vehicle using the ignition, this software error can, in rare cases, disable the vehicle?s electronic brake assist and illuminate the ESC, ABS and BRAKE telltales. This occurs at startup and the telltales are illuminated before the driver puts the vehicle into gear. Dealers will reprogram the brake system control module.
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.
PIT5730A2020-03-09. Service bulletin. ELECTRICAL SYSTEM. This Preliminary information communicates repair information on Service Brake System, Reduced Engine Power, and Speed Limited messages on the DIC. Along with these messages, a SES MIL will be on and the brake pedal may feel hard. When checking for DTC's the Brake System Control Module (BSCM) with have set a P0606 and C0021. Dealers are to reprogram the BSCM with updated calibrations to correct the concern.
PIP5667B2020-03-09. Service bulletin. FUEL SYSTEM, DIESEL. This Preliminary information communicates the part restriction for the diesel engine air delivery and exhaust system components
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.
PIT57322020-03-09. Service bulletin. FUEL SYSTEM, DIESEL:STORAGE:TANK ASSEMBLY. 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."

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