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

Bulletins, newest first
N2524940032025-05-23. Service campaign. ENGINE. Certain vehicles listed above, may have a condition where the connecting rod and/or crankshaft engine components in these vehicles may have manufacturing defects that can lead to engine damage and engine failure. This special coverage covers if an engine failure occurs in the vehicle as a result of the condition described above for a period of 10 years or 150,000 miles (240,000 km), whichever occurs first, from the date the vehicle was originally placed in service, regardless of ownership. For vehicles covered by Vehicle Service Contracts, all eligible claims with repair orders on or after May 23, 2025, are covered by this special coverage and must be submitted using the labor operation codes provided with this bulletin. Claims with repair orders prior to May 23, 2025, must be submitted to the Service Contract provider. Vehicle owners or lessees who paid for repairs referenced in this Special Coverage (“Customers”) are eligible for reimbursement of their reasonable and customary expenses in accordance with the procedures specified below. The conditional right to reimbursement is provided by GM solely in the interest of customer satisfaction and is personal to Customers. Customers may not assign and GM does not consent to any assignment of any Customer’s right to submit reimbursement claims, or to receive reimbursement, or any other rights granted by this Special Coverage to any third party, including but not limited to service contract providers, and this Special Coverage is not intended to and does not confer any third party beneficiary, subrogation or contribution rights, or any other rights to reimbursement, against GM, whether in law, equity or otherwise, on any third parties. Dealers are to replace the engine. The repairs will be made at no charge to the customer.
PIP5865D2025-05-19. Service bulletin. UNKNOWN OR OTHER. This Preliminary information communicates the possibility of DTC P30BF failing on low mile vehicles due to the possibility of the cylinder 1/2 sliding barrel binding on intake camshaft.
PIP5810C2025-05-19. Service bulletin. UNKNOWN OR OTHER. This Preliminary information communicates that the tool for the HD transfer cases to install the input seal during a repair is incorrect and a new tool is in development.
13-02-32-001H2025-05-06. Service bulletin. STEERING. This service bulletin provides a procedure to flush and bleed power steering system to correct a power steering noise or fluid leak concern that is caused during extremely low temperatures.
07-00-89-037W2025-05-05. Service bulletin. UNKNOWN OR OTHER. This warranty administration bulletin provides policy information for GM courtesy transportation and roadside assistance programs.
25-NA-0872025-05-02. Service bulletin. ELECTRICAL SYSTEM. This service bulletin provides information on the proper Reflective High Temperature Heat and/or Insulating Tape to use for certain repairs, such as Wiring Harness Repairs.
22-NA-1832025-05-01. Service bulletin. WHEELS. This service bulletin advises the technician of a different tire/rim option that can be used to correct a customer concern of poor ride quality at highway speeds.
21-NA-1392025-05-01. Service bulletin. ELECTRICAL SYSTEM; ENGINE. This service bulletin provides a repair procedure to correct a customer concern of a Malfunction Indicator Lamp (MIL) Illuminated - DTC P3055 Set.
25-NA-0802025-04-29. Service bulletin. POWER TRAIN. This service bulletin provides a procedure to overhaul the control valve to replace a plate and worn down check ball to correct the customers concern of No Reverse, No Shift Past Third Gear - DTC P2732 Set.
PIT6110F2025-04-29. Service bulletin. UNKNOWN OR OTHER. This Preliminary information communicates an issue with the SES MIL and DTC P062B /P060C and engineering is currently investigating.
25-NA-0762025-04-29. Service bulletin. ENGINE. This informational bulletin advises the technician that the gasket for the timing chain tensioner is not required.
PIP5863C2025-04-29. Service bulletin. UNKNOWN OR OTHER. This Preliminary information communicates to dealers’ information related to a Malfunction Indicator Lamp (MIL) Illuminated due to a U0672 setting. Advises the technician to perform Electric Engine Coolant Pump connection inspections. To clear the code to see if it resets current. If the code resets it advises to utilize Strategy Based Diagnosis. If the code does not reset, it advises to release the vehicle to the customer and that GM is aware of this issue.
PIP6008E2025-04-28. Service bulletin. UNKNOWN OR OTHER. This Preliminary information communicates a possible retainer ring dis-lodged for a DTC P2714, may not have reverse as well.
PIP5926D2025-04-28. Service bulletin. UNKNOWN OR OTHER. This Preliminary information communicates that the t-case input seal, and/or the o-ring most likely is the source of the leak between the transmission and the t-case.
25-NA-0522025-04-28. Service bulletin. ENGINE. This bulletin advises the technician to flush the cooling system multiple times if oil has been found in the cooling system and replace the parts that may be contaminated due to oil in system.
23-NA-1852025-04-28. Service bulletin. POWER TRAIN; ELECTRICAL SYSTEM; STEERING. This service bulletin helps diagnose/reduce possible CCND issues on Transfer Cases - Service 4WD on DIC, Intermittent Failures, Noise Concerns, Driveline/Steering Vibration/Shudder, Intermittent DTCs/MIL Illuminated, Engagement/Disengagement/Ratcheting Concerns.
13-08-116-001K2025-04-25. Service bulletin. ELECTRICAL SYSTEM. The intent of this service bulletin is to identify aftermarket ALDL or DLC interface devices as potential sources for causing multiple customer concerns that do not have other diagnostic methods to identify them.
07-08-42-006T2025-04-25. Service bulletin. EXTERIOR LIGHTING. This service bulletin provides technicians with information on available BCM calibrations to restore bulb outage detection on vehicles produced by a second stage manufacturer (Upfitter), and/or turn signals flash fast after factory box removed.
24-NA-0982025-04-24. Service bulletin. ELECTRICAL SYSTEM; UNKNOWN OR OTHER. This service bulletin provides information for dealers/technicians on Service Programming System (SPS) Error Codes E4398, E4399, E4401, E4403, M4404, M4413, M6954, M6955, E4414, E4423, E4491, E4492, or E6961 and resolution information.
25-NA-0652025-04-24. Service bulletin. STEERING; SERVICE BRAKES; FUEL/PROPULSION SYSTEM. This informational bulletin instructs the tech when fuel/fluid is needed to be tested and where it can be sent for analysis.
24-NA-2472025-04-16. Service bulletin. ENGINE. This informational bulletin advises the technician of which pan to use if the LCE has been replaced and to install an aluminum pan should be used with a new LCE.
15-06-03-001F2025-04-15. Service bulletin. ELECTRICAL SYSTEM. This service bulletin provides information to diagnose batteries that have set for a long period of time and/or cold weather climates and testing those batteries.
08-03-10-006I2025-04-15. Service bulletin. WHEELS. This service bulletin provides a procedure on how to clean and resurface aluminum wheel bead seats for vehicles that have the condition of Tire Slowly Goes Flat, Tire Air Loss, Low Tire Pressure Warning Light Illuminated, Aluminum Wheel Bead Seat Corrosion.
PIT5551R2025-04-15. Service bulletin. UNKNOWN OR OTHER. This Preliminary information communicates a "Forward Collision System Reduced" message displayed on the DIC when the Forward Automatic Braking has been set to the "Alert" setting. This is normal when the FAB has been set to "Alert".
PIT5986D2025-04-15. Service bulletin. UNKNOWN OR OTHER. This Preliminary information communicates a diagnostic tip for a thump, click, pop, clunk type noise that is heard from the front end. Dealers are to inspect for something contacting the grill shutters as they open and close.

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