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
| 16NA109 | 2021-05-03. Service bulletin. STEERING. This service bulletin provides a procedure inspecting for excess grease or Sealant on the Exterior of the steering gear due to seeing grease or sealant on certain locations on the gear. |
|---|---|
| N212330530 | 2021-04-26. Service bulletin. WHEELS. Customer Satisfaction Program. Certain vehicles may have had a double charge applied for the 20-inch aluminum wheels with accents at the time of vehicle purchase. Dealers will provide the customer with a reimbursement check in the amount of $1400 for 2500HD models OR $800 for 3500HD models. |
| N202324120 | 2021-04-26. Service bulletin. SERVICE BRAKES. Customer Satisfaction Program. On certain vehicles may experience brake function issues over time based on feedback received from the supplier concerning the condition of certain eBoost brake unit assemblies. Dealers are to replace the eBoost brake unit assembly. |
| N212328090 | 2021-04-26. Service bulletin. POWER TRAIN:AUTOMATIC TRANSMISSION. Customer Satisfaction Program. Certain 2021 model year Chevrolet Silverado 1500 and GMC Sierra 1500 vehicles, equipped with an 8 speed automatic transmission, (RPO MQE), may have a broken reaction carrier in the transmission. Dealers will replace the transmission. |
| N232329330 | 2021-04-26. Service bulletin. EQUIPMENT. Customer Satisfaction Program. Certain vehicles may have a cargo tie down ring made incorrectly available for ordering at the time of vehicle purchase. This cargo tie down ring accessory (RPO 5VI) is only designed to work with a Steel Bed and not a Carbon Pro Bed. Dealers will provide the customer with a reimbursement check in the amount of $100. |
| PIP5798 | 2021-04-19. Service bulletin. SUSPENSION; STRUCTURE. This Preliminary information communicates Some customers may comment about a rough idle and/or vibration at idle. This condition may be most noticeable when the engine is completely warmed up and accessories are off, you may also feel this while idling at a stop in Drive. May feel like a misfire, stumble, lopey or lumpy idle or may be described as a low idle. This concern may be caused by several potential causes: Misfire and/or base engine concern Wrong fuel used (regular instead of premium when required) Idle speed fluctuation Engine mount pre-load |
| PIT5791A | 2021-04-19. Service bulletin. EQUIPMENT:ELECTRICAL:RADIO/TAPE DECK/CD ETC.; BACK OVER PREVENTION:SOFTWARE. This Preliminary information communicates a condition where the radio may display a :connection not availale, please call OnStar agent". This bulletin advises that Engineering is working on a software solution that will prevent the message from displaying when listening to non-SXM sources, but still allow the message to display when a loss of connectivity exists and the user is attempting to play Sirius XM. |
| PIT5829 | 2021-04-19. Service bulletin. BACK OVER PREVENTION:DISPLAY FUNCTION; EQUIPMENT:ELECTRICAL:RADIO/TAPE DECK/CD ETC.. This Preliminary information communicates a condition where the the customer may see a SD card remove message accompanied by a 0X40000 code on the DIC or radio display. This PI offers some testing tips and advises on direction depending on the tests and procedures outlined in the PI |
| PIP5795 | 2021-04-19. Service bulletin. STRUCTURE:BODY. This Preliminary information communicates to technicians to replace the rear cover with seal in the event of a rear oil seal leak. |
| PIP5212C | 2021-04-19. Service bulletin. ENGINE AND ENGINE COOLING. This Preliminary Information communication provides information to the technician about vehicles that have run hot and or has a tick noise. Technician should inspect the head gaskets to ensure are not installed backwards. Technician should replace the head gasket if they are found installed backwards. |
| PIT5828 | 2021-04-19. Service bulletin. TRAILER HITCHES. 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. |
| PIP5712B | 2021-04-19. Service bulletin. ENGINE AND ENGINE COOLING:ENGINE:CRANK/CAMSHAFT POSITION SENSOR; POWER TRAIN. This Preliminary information communicates to the technician a service Diagnostic / Repair tip to avoid causing the crankshaft sprocket to disengage from the crankshaft during crankshaft balancer or cam drive system component related service procedures. |
| PIP5793 | 2021-04-19. Service bulletin. EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL. This Preliminary information communicates Information on AFM/DFM usage for 2021 MY pickups |
| PIP5794 | 2021-04-19. Service bulletin. POWER TRAIN. This Preliminary information communicates diagnostics to the dealer involving a vehicle shudder concern caused by the camshaft actuator system that can be mistaken for a transmission issue. |
| PIT5818 | 2021-04-19. Service bulletin. VEHICLE SPEED CONTROL; STEERING. This Preliminary information communicates an issues will low or poor heater performance on the drivers side. Dealers are to inspect the HVAC temperature door linkage and if ok replace the heater core. |
| PIP5745A | 2021-04-19. Service bulletin. EQUIPMENT. This Preliminary information communicates to technicians a possible cause and correction for a P026A |
| PIP5791 | 2021-04-19. Service bulletin. ENGINE AND ENGINE COOLING. This Preliminary information communicates to dealership technicians to perform a sweep of the coolant flow control valve and test the circuits before replacing the Engine Coolant Flow Control Valve, and to assist engineering in root causing the P2B60. |
| PIP5787A | 2021-04-19. Service bulletin. BACK OVER PREVENTION; SERVICE BRAKES. This Preliminary information communicates Some customers may comment that the SES lamp is illuminated or was Illuminated and turned off. During inspection Technician may notice DTC, P0106 (Manifold Absolute Pressure Sensor Performance), P0108 (Manifold Absolute Pressure Sensor Circuit High) and/or P00C7 (Intake Air Pressure Measurement System Sensor and Multiple Sensors Correlation) codes active or stored in history. This condition may be caused by a faulty Manifold Absolute Pressure (MAP) sensor. |
| PIP5792 | 2021-04-19. Service bulletin. FUEL SYSTEM, GASOLINE; POWER TRAIN. This Preliminary information communicates to the dealer technician that if a customer comments that their vehicle equipped with a 6L80, 6L90, 8L90, 10L80, or 10L1000 transmission has a harsh shift, shudder or stall concern they should inspect for a twisted transmission cooler line. Technicians are instructed to disconnect the cooler line and untwist it then reconnect the cooler line and inspect the cooler line for being misshaped. Technicians are instructed to replace the cooler line if it is misshaped. |
| PIT5715A | 2021-04-19. Service bulletin. POWER TRAIN. This Preliminary Information provides information to the technician about a additional diagnostic tip for a check engine lamp for DTC P3055 and P3056 and the start/Stop being inoperative. |
| PIP5787 | 2021-04-19. Service bulletin. SERVICE BRAKES; BACK OVER PREVENTION. This Preliminary information communicates Some customers may comment that the SES lamp is illuminated or was Illuminated and turned off. During inspection Technician may notice DTC, P0106 (Manifold Absolute Pressure Sensor Performance), P0108 (Manifold Absolute Pressure Sensor Circuit High) and/or P00C7 (Intake Air Pressure Measurement System Sensor and Multiple Sensors Correlation) codes active or stored in history. This condition may be caused by a faulty Manifold Absolute Pressure (MAP) sensor. |
| PIC6425C | 2021-04-19. 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. |
| PIP5788 | 2021-04-19. Service bulletin. EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL. This Preliminary information communicates Some customers may comment that the SES lamp is illuminated or was Illuminated and turned off, with no driveabilty concerns. During inspection Technician may notice DTC P2635. Unknown at this time engineering is working on this concern |
| PIT5803A | 2021-04-19. 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 |
| PIP5712A | 2021-04-19. Service bulletin. ENGINE AND ENGINE COOLING:ENGINE:CRANK/CAMSHAFT POSITION SENSOR. This Preliminary information communicates to the technician a service Diagnostic / Repair tip to avoid causing the crankshaft sprocket to disengage from the crankshaft during crankshaft balancer removal. |
The summaries are NHTSA's. Each bulletin's page links NHTSA's copy of the manufacturer's document.