WenmarOpen by Wenmar Pro

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: Body and frame are shown. Show all

Bulletins, newest first
PIP5655E2021-04-19. Service bulletin. STRUCTURE. This Preliminary information communicates to the dealer technician that the 10L1000 transmission and valve body assembly part restriction has ended. Dealers are advised that these transmissions and valve bodies can now be ordered through the regular GM CCA parts process or PQC process for required dealers (Canada).
PIP5776B2021-04-19. Service bulletin. STRUCTURE. This Preliminary information communicates that a vehicle may exhibit a misfire condition resulting in misfire codes P0300-P308. Upon diagnosis it may be discovered the lifter has come apart. It is recommended to replace the lifter guide and the four lifters.
PIP57842021-04-19. Service bulletin. STRUCTURE. This Preliminary information communicates to the dealer technician to inspect for a missing 1-2-7-8-R clutch fluid passage seal or incorrect 1-2-7-8-R clutch fluid passage seal being install for a no movement concern after valve body replacement on the 8L45 or 8L90 transmissions.
PIP5771B2021-04-19. Service bulletin. POWER TRAIN; STRUCTURE. This Preliminary information communicates to the dealer technician to replace the valve body on 8 speed transmissions setting DTC P0796 if no debris is found in the transmission fluid pan. If debris is found in the transmission fluid pan the technician is advised to repair the transmission as needed and replace the valve body.
21NA0262021-03-08. Service bulletin. EQUIPMENT; STRUCTURE; EQUIPMENT ADAPTIVE/MOBILITY. This service bulletin provides information for dealers/technicians on accessory all-weather floor liners and flat mats warped or misshapen.
20NA1752021-02-22. Service bulletin. STRUCTURE:BODY. This technical bulletin provides repair information to correct a customer concern of vertical misalignment between cab and pickup box on driver side of vehicle.
19NA2572021-02-22. Service bulletin. STRUCTURE. This technical bulletin provides repair information to correct a customer concern of the pickup box being out of alignment.
20NA1752021-02-01. Service bulletin. STRUCTURE. This technical bulletin provides repair information to correct a customer concern of vertical misalignment between cab and pickup box on driver side of vehicle.
19NA2572021-02-01. Service bulletin. STRUCTURE; EQUIPMENT. This technical bulletin provides repair information to correct a customer concern of the pickup box being out of alignment.
990851001E2020-12-21. Service bulletin. EQUIPMENT; STRUCTURE. Thins informational bulletin provides information on Paint-less Dent Repair Process.
18NA3062020-10-26. Service bulletin. EQUIPMENT; STRUCTURE:BODY. This Warranty Administration bulletin provides information for dealers/Service advisors on when and how to submit a Pre-Repair Authorization (PRA) (US dealers only).
PIT5709A2020-10-19. Service bulletin. STRUCTURE. This Preliminary information communicates the need for proper documentation when submitting a Field Product Report on paint issues with the new HD Silverado and Sierra.

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