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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: Equipment and accessories are shown. Show all

Bulletins, newest first
080730035E2021-08-09. Service bulletin. EQUIPMENT; EQUIPMENT ADAPTIVE/MOBILITY; POWER TRAIN. This bulletin provides information on the harmful effects of water or ethylene glycol in transmission fluid.
010842001N2021-08-09. Service bulletin. EXTERIOR LIGHTING; EQUIPMENT ADAPTIVE/MOBILITY; EQUIPMENT. This service bulletin provides information for dealers/technicians on Exterior Lamp Condensation and Water Leaks and Replacement Guidelines.
21NA1522021-08-09. Service bulletin. VISIBILITY:GLASS, SIDE/REAR; EQUIPMENT. This service bulletin provides information for dealers/technicians on glass ultraviolet (UV) Ray protection and tint percentage.
21NA1452021-08-09. Service bulletin. EQUIPMENT ADAPTIVE/MOBILITY; ELECTRICAL SYSTEM:SOFTWARE; EQUIPMENT. This service bulletin provides U157 software update information to correct customer concerns of radio Software related issues.
21NA0952021-08-09. Service bulletin. EQUIPMENT; ENGINE AND ENGINE COOLING:EXHAUST SYSTEM. This technical bulletin provides a procedure to seal the exhaust at the UFSCR and Tailpipe flange.
120851002M2021-08-09. Service bulletin. EQUIPMENT. This informational bulletin provides technicians and dealership personnel with spray-in bed liner general information and repair procedures.
120851002L2021-08-09. Service bulletin. EQUIPMENT. This informational bulletin provides technicians and dealership personnel with spray-in bed liner general information and repair procedures.
100089006H2021-08-09. Service bulletin. EQUIPMENT. This service bulletin provides information for dealers on how to submit a product information report (PIR) (Canada Only).
070089037Q2021-08-09. Service bulletin. EQUIPMENT. This warranty administration bulletin provides policy information for GM courtesy transportation and roadside assistance programs.
070089037P2021-08-09. Service bulletin. EQUIPMENT. This warranty administration bulletin provides policy information for GM courtesy transportation and roadside assistance programs.
21NA1102021-07-19. Service bulletin. EQUIPMENT. This informational bulletin provides information for dealers/technicians on Information on GM Accessories - Instructions on Claim Submission on Dealer-Replaced Tonneau Covers During Warranty Period.
20NA1592021-07-19. Service bulletin. EQUIPMENT. This Warranty Administration bulletin is for information on General Motors New Vehicle Tire Warranty Program (U.S. Dealers Only).
19NA0762021-07-19. Service bulletin. ELECTRICAL SYSTEM; EQUIPMENT. This service bulletin provides repair information to correct a customer concern of Blue or Black Screen and Service Rear Vision System Message on Radio Display Shifting into Reverse.
18NA3062021-07-19. Service bulletin. EQUIPMENT. This Warranty Administration bulletin provides information for dealers/Service advisors on when and how to submit a Pre-Repair Authorization (PRA).
21NA1102021-07-06. Service bulletin. EQUIPMENT. This informational bulletin provides information for dealers/technicians on Information on GM Accessories - Instructions on Claim Submission on Dealer-Replaced Tonneau Covers During Warranty Period.
18NA3062021-07-06. Service bulletin. EQUIPMENT. This Warranty Administration bulletin provides information for dealers/Service advisors on when and how to submit a Pre-Repair Authorization (PRA).
PIT5746A2021-06-14. Service bulletin. EQUIPMENT. This Preliminary information communicates information on how dealers can contact the supplier for Associated Accessories offered through GM.
PIT5839A2021-06-14. Service bulletin. EQUIPMENT:APPLIANCE:TV/RADIO/SPEAKERS; EQUIPMENT. This Preliminary information communicates to GM dealers that the above mentioned concern is software related and that General Motors is working on a solution.
070089036J2021-06-07. Service bulletin. EQUIPMENT. This service bulletin provides information on Enhancing Field Product Reports with Digital Pictures.
020089002T2021-06-07. Service bulletin. EQUIPMENT. This service bulletin provides information for dealers/technicians on When and How to Submit a Field Product Report (FPR) (U.S. Dealers Only).
N2023096302021-05-24. Service bulletin. EQUIPMENT. Customer Satisfaction - Certain 2020 model year Chevrolet Silverado 1500 and Sierra 1500 vehicles are equipped with trailering information labels that incorrectly state the vehicle?s trailering capabilities. Install the overlay labels. Because these labels can easily be installed by the customer, and to reduce their inconvenience, labels and installation instructions will be mailed to customers of record.
21NA1032021-05-24. Service bulletin. EQUIPMENT. This service bulletin provides information regarding Witness Marks from Panel Adjustments Made During Manufacturing and that it is considered a normal condition.
21NA0972021-05-24. Service bulletin. EQUIPMENT:APPLIANCE:ELECTRIC WATER HEATER. This technical bulletin provides a procedure to install a pice of foam between the heater core pipes to correct the customers concern.
21NA0682021-05-24. Service bulletin. EQUIPMENT:ELECTRICAL. 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 (U.S. Only).
20NA0382021-05-24. Service bulletin. EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL. This informational bulletin explains the difference in AFM and DFM engines and what is and is not activated during this occurrence.

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