2021 GMC Sierra 2500 Technical Service Bulletins

1,059 technical service bulletins (TSBs) are on record for the 2021 GMC Sierra 2500. TSBs are notes manufacturers send to dealers about repair procedures for issues seen in the field. They are not recalls and do not by themselves mean a vehicle has a fault.

• 11037555Sep 26, 2026Other or unknown. This PI provides Diagnostics tips on how the LIN bus works and how to diagnosis it.
• 11037253Sep 4, 2026Other or unknown. This preliminary information advises a dealer on how to email GDS2 session logs into Technical Assistance.
• 11036713Aug 27, 2026Other or unknown. This document assists GM dealer technicians with diagnosing torque converter concerns to ensure torque converter replacement is necessary. The torque converter part number will be placed on order restriction, and the technician will be asked to follow 25-NA-148 before requesting a part through PQC.
• 11036392Aug 20, 2026Other or unknown. This Preliminary information communicates to dealer to perform a MEC reset for wireless projection issues
• 11036196Aug 7, 2026Other or unknown. This Preliminary information communicates an issue where an aftermarket autostop device or rear taillights is causing a dead battery.
• 11035350Jul 23, 2026Other or unknown. This PI provides information to repair the door water deflector which is not sealed properly allows water into the door jam/sill area.
• 11035340Jul 21, 2026Other or unknown. PI to help diagnose A/C concern
• 11035308Jul 21, 2026Other or unknown. This PI provides diagnostic tips for diagnosing electric trailer brakes issues.
• 11035133Jul 17, 2026Other or unknown. This PI was created to help avoid unnecessary front camera module replacements
• 11034977Jul 6, 2026Other or unknown. The purpose of this PI is to inform dealer technicians of a normal cab pressure relief valve noise to avoid unnecessary part replacement
• 11034767Jun 24, 2026Other or unknown. This Preliminary information communicates information on a hydraulic rush type noise from the power steering gear. This noise is a characteristic of the new Active Hydraulic Assist System RPO NV8 and no repairs should be made. The noise is most noticeable in the cab at idle, in park, with all accessories turned off.
• 11034769Jun 23, 2026Other or unknown. This Preliminary information communicates an issue with an OTA pending message still displayed after an OTA event and how to reset/clear the message.
• 11034001Jun 10, 2026Other or unknown. This PI provides diagnostic steps for dealer technicians to verify the condition and ensure that part replacement is necessary
• 11033986Jun 9, 2026Other or unknown. This Preliminary information communicates an issues with the HVAC making a hum buzz noise when the blower is set to a higher speed. Engineering is working on a new HVAC door seal material to correct the noise.
• 11032777May 14, 2026Other or unknown. This PI provides diagnostic tips for diagnosing electric trailer brakes issues.
• 11032925May 12, 2026Other or unknown. • Improvements to OnStar functionality.
• 11032764May 11, 2026Other or unknown. Pi created to provide GM dealers with information on gathering information for projection issue
• 11032763May 11, 2026Other or unknown. This Preliminary information communicates to dealer to perform a MEC reset for wireless projection issues
• 11031509Apr 13, 2026Other or unknown. This Preliminary information communicates that some customers may comment that after an auto-stop event the engine does not restart and to inspect the engine ground strap. Temporarily on hold while PIE0572 is active. PIE0572 has now ended and reinstating the PI.
• 11030974Apr 1, 2026Other or unknown. This preliminary information communicates information about how to determine if a wheel and tires size change is available.
• 11030353Mar 24, 2026Other or unknown. This PI was created to help avoid unnecessary front camera module replacements
• 11030532Mar 21, 2026Other or unknown. Improvements to OnStar functionality.
• 11030169Mar 13, 2026Other or unknown. This PI was created to help avoid unnecessary front camera module replacements
• 11030170Mar 12, 2026Other or unknown. This PI was created to help avoid unnecessary front camera module replacements
• 11030097Mar 9, 2026Other or unknown. This Preliminary Information communicates direction for different audio issues with RPO UQA, UQF, UQS, or NKD
• 11030092Mar 9, 2026Other or unknown. This Preliminary information communicates the steps on how to save a GDS2 Session Log and upload to a Technical Assistance Case in CX Connect.
• 11030091Mar 9, 2026Other or unknown. This preliminary information advises a dealer on how to email GDS2 session logs into Technical Assistance.
• 11029950Mar 2, 2026Other or unknown. This Preliminary information communicates to the field on how to diagnosis a GPS issue with the Telematic module with no DTC'ss
• 11029454Feb 26, 2026Other or unknown. This preliminary information communicates an issue with the engine running after the ignition is turned off and diagnostic help to isolate a possible Fuel Pump Control Module issue.
• 11029441Feb 26, 2026Other or unknown. This Preliminary information communication provides information to the technician on installing Regular Production Option Code UVC Rearview Camera. Technician will need to reference the latest version of General Motors Up-fitter Integration Bulletin 152. The information can be found at http://www.gmupfitter.com/ under the "Technical Bulletin" Tab and then "Show all bulletins."
• 11029298Feb 26, 2026Other or unknown. This Preliminary information communicates information on how to disable the Side Blind Zone Detection and Park Assist systems when a customer removes the pickup box from the vehicle to install an aftermarket bed or body.
• 11028931Feb 16, 2026Other or unknown. This Preliminary Information communication provides information to the technician that some owners of Heavy Duty Trucks and Utilities may ask if they can lower their tire pressures. Tire pressures being set to the "Tire and Loading Label" will ensure the safe handling and ride characteristics of the truck and should not be lowered.
• 11028977Feb 5, 2026Other or unknown. Improvements to OnStar functionality. During the update process, your radio may stay on up to 5 minutes after you exit the vehicle. This is expected behavior when an update package is onboard the vehicle. Do not service your vehicle during installation.
• 11028700Feb 5, 2026Other or unknown. This preliminary information communicates an issue with aftermarket LED headlights causing IPC warning messages and MIL along with several low speed lan DTCs.
• 11027698Jan 16, 2026Other or unknown. This PI Communications information on an alternative product dealers can use to perform 19-NA-255: Wax Coating on Frame Peeling, Metal Shows Corrosion/Rusting due to issue with getting product from current supplier listed in the bulletin.
• 11027697Jan 16, 2026Other or unknown. This Preliminary information communicates to the field on how to diagnosis a GPS issue with the Telematic module with no DTC's
• 11027692Jan 15, 2026Other or unknown. This Preliminary information communicates an issue with blower motor speed changing when air flow is blocked by snow.
• 11027701Jan 14, 2026Other or unknown. This PI advised dealer technicians of possible causes of diesel fuel contamination in gasoline powered vehicles and advises of warranty direction.
• 11027601Jan 8, 2026Other or unknown. This preliminary information advises a dealer on how to email GDS2 session logs into Technical Assistance.
• 11027600Jan 7, 2026Other or unknown. This Preliminary Information communication provides information to the technician about customers that may request the factory Integrated Trailer Brake Controller Regular Production Option Code (JL1) be installed on their Full-Size Pickup or SUV when the vehicle was not ordered with the option. Dealer should advise the customer it cannot be added to the vehicle.
• 11027598Jan 5, 2026Other or unknown. This Preliminary information communicates an issue with a service keyless entry message caused by aftermarket door handle covers and they should be removed.
• 11026924Dec 30, 2025Other or unknown. This Preliminary information communicates that some customers may comment that after an auto-stop event the engine does not restart and to inspect the engine ground strap. Temporarily on hold while PIE0572 is active. PIE0572 has now ended and reinstating the PI.
• 11026071Nov 26, 2025Other or unknown. This Preliminary information communicates an issues with the HVAC making a hum buzz noise when the blower is set to a higher speed. Engineering is working on a new HVAC door seal material to correct the noise.
• 11025755Nov 20, 2025Other or unknown. This Preliminary Information communication provides information to the technician about vehicles that have had multiple repair attempts that are being performed on customer’s vehicles that exhibit vibration conditions without utilizing the support of General Motors Technical Assistance Center.
• 11025492Nov 6, 2025Engine. Under Field Actions N252494000, N252494001, the service procedure includes performing a PICO test on vehicle engines within the identified suspect VIN population. If the engine passes the PICO test, the engine oil will be changed from 0W20 to Mobil 1 Supercar 0W40 dexosR. From that point forward, the engine must use 0W40 dexosR oil products for all future oil change services.
• 11024703Oct 22, 2025Other or unknown. This Preliminary information communicates an issues with the HVAC making a hum buzz noise when the blower is set to a higher speed. Engineering is working on a new HVAC door seal material to correct the noise.
• 11024460Oct 18, 2025Other or unknown. This Preliminary information communicates to the field on how to diagnosis a GPS issue with the Telematic module with no DTC's
• 11024455Oct 17, 2025Other or unknown. This Preliminary information communicates to the field on how to diagnosis a GPS issue with the Telematic module with no DTC's
• 11024458Oct 16, 2025Other or unknown. This Preliminary information communicates to dealer to perform a MEC reset for wireless projection issues
• 11024189Oct 9, 2025Transmission and drivetrain. Certain vehicles listed above, may have a condition where the transmission control valve has worn, resulting in a gradual loss of pressure within the valve. The effects can cause harsh shifting, setting a service engine soon message, reduced engine performance or P0747 diagnostic trouble code. Dealers are to install a new control valve body. The repairs will be made at no charge to the customer.

← All problems reported for the 2021 GMC Sierra 2500