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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
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.
20NA1592021-02-01. Service bulletin. TIRES. This Warranty Administration bulletin is for information on General Motors New Vehicle Tire Warranty Program (U.S. Dealers Only).
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.
19NA2182021-02-01. Service bulletin. EQUIPMENT ADAPTIVE/MOBILITY; EQUIPMENT; ENGINE AND ENGINE COOLING. This technical bulletin provides a service procedure to correct a condition of Ticking Noise from the Engine.
19NA1362021-02-01. Service bulletin. PARKING BRAKE; EQUIPMENT; POWER TRAIN:TRANSFER CASE (4-WHEEL DRIVE). This service bulletin provides a diagnostic procedure to aid in correcting a customer concern of a Howling, Whining/Whirring Noise, Shudder/Vibration and/or Grinding Noise While in 4HI, 4HI Auto and/or During Parking Lot Maneuvers in Auto Mode.
18NA3062021-02-01. Service bulletin. EQUIPMENT. This Warranty Administration bulletin provides information for dealers/Service advisors on when and how to submit a Pre-Repair Authorization (PRA).
17NA1662021-02-01. Service bulletin. EQUIPMENT; ENGINE AND ENGINE COOLING. This technical bulletin provides a procedure to measure vibration and install engine mounts to correct a Rough Idle in Drive concern.
16NA0192021-02-01. Service bulletin. POWER TRAIN; ELECTRICAL SYSTEM:SOFTWARE. This informational bulletin provides information on Transmission Adaptive Functions and Correcting Low Mileage Harsh Shifts, Slips, or Flares.
N202319660 012021-02-01. Service bulletin. ENGINE AND ENGINE COOLING; EQUIPMENT; EQUIPMENT ADAPTIVE/MOBILITY. Service Update. Certain vehicles may present a broken engine valve spring. This may cause the engine to run rough, an engine knocking or ticking noise, a check engine light illumination, or a possible vehicle stall. Dealers are to perform the inspection procedure contained within this bulletin.
N2023205102021-02-01. Service bulletin. EQUIPMENT ADAPTIVE/MOBILITY; ENGINE AND ENGINE COOLING; EQUIPMENT. Customer Satisfaction Program. Certain vehicles, equipped with a gas engine, may have a condition in which the printed circuit board inside of the water pump may have been manufactured incorrectly potentially causing a water pump failure. The vehicle coolant system temperature is monitored and will display multiple warnings to the customer as coolant temperatures rise. At a set coolant temperature, the MIL will illuminate, DTC P2B85 will set in the engine control module (ECM), the oil pressure gauge will indicate high oil pressure and reduced torque with notification to the driver of reduced power will occur. If the customer continues to drive after this warning and the coolant temperature continues to rise, a chime will occur, the AC will be disabled and an additional message instructing the driver to idle will illuminate. If the customer continues to drive the vehicle after all previous warnings and the coolant temperature continues to rise a message the engine will shut down could occur, and the engine will be shut down. Dealers are to replace the water pump.
PIC6425A2021-01-25. Service bulletin. BACK OVER PREVENTION:SOFTWARE. This Preliminary information communicates A list of software concerns and advises that engineering is working on a resolution. This PI will be changed to a bulletin once the Software is released.
PIC64252021-01-25. Service bulletin. BACK OVER PREVENTION:SOFTWARE. This Preliminary information communicates A list of software concerns and advises that engineering is working on a resolution. This PI will be changed to a bulletin once the Software is released.
PIT58032021-01-25. Service bulletin. AIR BAGS. This Preliminary information communicates to dealers there is a known condition with being able to set the Teen Driver PIN and that General Motors Engineering team is working on a correction
PIP5733G2021-01-25. Service bulletin. ENGINE AND ENGINE COOLING:ENGINE:CRANK/CAMSHAFT POSITION SENSOR. This Preliminary information communicates Possible Crank no start or extended crank with DTC p12A6 set current or history. Under Investigation
PIT5799A2021-01-25. Service bulletin. EQUIPMENT:ELECTRICAL:RADIO/TAPE DECK/CD ETC.. This Preliminary information communicates a cocnern where a flashing spot can intermittently show up on the radio display while in reverse. The PI advises that engineering is investigating the concern.
PIT5751C2021-01-25. Service bulletin. ELECTRICAL SYSTEM:WIRING. This Preliminary information communicates and issue with the SES MIL on setting DTC's P0201/P0202/P0203/P0204/P0205/P0206/P0216 and instructing dealership to inspect the engine wiring harness for damage.
PIT5793A2021-01-25. Service bulletin. BACK OVER PREVENTION:SOFTWARE. This Preliminary information communicates that engineering is Work on a Software fix for some radio apps not Opening, Connected Navigation (live traffic, etc.) is not functioning (base navigation functions correctly)
PIT5479D2021-01-25. Service bulletin. ENGINE AND ENGINE COOLING. This Preliminary Information communication provides information to the technician about fluid leaking from the brake caliper piston area found during a service of the vehicle. The substance is actually excess assembly grease from the caliper boot and piston installation. This grease can be cleaned off and the rest of the service completed.
PIT5386F2021-01-25. Service bulletin. ELECTRICAL SYSTEM; BACK OVER PREVENTION. This Preliminary Information communication provides information to the technician about vehicles that are found to have a back-up alarm inoperative during the Pre-Delivery Inspection. On trucks equipped with the Back Up Alarm (RPO 8S3), the alarm will be intentionally left disconnected from the assembly plant. Technician will reroute the harness and plug it in.
PIP5764A2021-01-25. Service bulletin. EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL. This Preliminary information communicates to the technician a possible cause of a P2B60 as terminal corrosiosn and provides a correction
PIC64232021-01-25. Service bulletin. EQUIPMENT:ELECTRICAL:INFOTAINMENT:BLUETOOTH/WIFI. This Preliminary Information communication requests information from the technician about vehicles that may have Bluetooth or phone projection issues. Dealer should request as much information from the customer on the concern as possible and fill in the questionaire.
PIT5789A2021-01-25. Service bulletin. ELECTRICAL SYSTEM:BODY CONTROL MODULE/BCM. This Preliminary information communicates an issues with an SES MIL and DTC P2B87 setting. Engineering is working on releasing updated BCM cals to correct the concern.
N2023196602020-12-21. Service bulletin. ENGINE; ELECTRICAL SYSTEM:SOFTWARE. Service Update. Certain vehicles may present a broken engine valve spring. This may cause the engine to run rough, an engine knocking or ticking noise, a check engine light illumination, or a possible vehicle stall. Dealers are to perform the inspection procedure contained within this bulletin.
PIE06012020-12-21. Service bulletin. ELECTRICAL SYSTEM; ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL. This engineering informational bulletin is requesting information from technicians to perform the check list provided and contact the engineer listed in regards to the Service Engine Soon Lamp being illuminated.
PIE0599A2020-12-21. Service bulletin. AIR BAGS. This engineering informational bulletin is requesting information from technicians to perform the check list provided and contact the engineer listed in regards to the airbag lamp illuminated on the driver?s information center (DIC).

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