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Service bulletins for the 2020 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.

1990 on file from NHTSA, as of 2026-10-19.

By type

By component

By trouble code

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Only bulletins with component: Transmission and driveline are shown. Show all

Bulletins, newest first
24-NA-2622025-12-03. Service bulletin. POWER TRAIN. This bulletin helps aid the tech in possible 10L100 transmission noise that may be normal or abnormal depending on the concern noted.
N242454441 -032025-10-09. Service campaign. POWER TRAIN. 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.
21-NA-2382025-07-07. Service bulletin. POWER TRAIN. This technical bulletin provides a procedure to inspect the front pump of the transmission for a possible leak.
PI0281L2025-06-12. Service bulletin. STEERING; POWER TRAIN; SUSPENSION. This preliminary informational (PI) bulletin provides information to dealership personnel that may be helpful when addressing underbody component corrosion with customers.
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.
PIP5966A2025-03-02. Service bulletin. POWER TRAIN. This Preliminary information communicates Diagnostic aids for a no start or DTC'S following a transmission replacement
PIP5966A2025-03-02. Service bulletin. POWER TRAIN. This Preliminary information communicates Diagnostic aids for a no start or DTC'S following a transmission replacement
24-NA-2642025-02-27. Service bulletin. POWER TRAIN. This bulletin helps aid the tech in possible noise that may be normal or abnormal depending on the concern noted.
16-NA-0192025-02-19. Service bulletin. POWER TRAIN. This service bulletin provides information on Transmission Adaptive Functions and Correcting Low Mileage Harsh Shifts, Slips, or Flares.
PIP5175F2025-02-10. Service bulletin. POWER TRAIN. This Preliminary Information communication provides information to the technician about vehicles that may have a delayed engagement into drive, shudder at a launch, or the transmission is slipping when shifting into 1st, 2nd, 3rd or 4th gears. This may be due to loose stator support to pump cover bolts causing a leak at the stator support to pump cover gasket. Technician will check for the bolts to be loose. If any of the bolts are loose or the gasket is misaligned or leaking, the transmission pump cover must be replaced and the 1234 clutch plates should be inspected for being distressed and repaired as needed.
N242454441-022025-01-28. Service campaign. POWER TRAIN. 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. This special coverage covers the condition described above for a period of 15 years or 150,000 miles (240,000km), 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 November 26, 2024, 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 November 26, 2024, 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 install a new control valve body. The repairs will be made at no charge to the customer.
09-06-04-026Z2025-01-23. Service bulletin. ENGINE; POWER TRAIN; ELECTRICAL SYSTEM. This bulletin provides information on identifying Non-GM Engine Calibrations for Gasoline Engines using the Tech 2 or GDS 2.
24-NA-2642024-12-20. Service bulletin. POWER TRAIN. This bulletin helps aid the tech in possible transmission noise that may be normal or abnormal depending on the concern noted.
24-NA-2622024-12-20. Service bulletin. POWER TRAIN. This bulletin helps aid the tech in possible transmission noise that may be normal or abnormal depending on the concern noted.
21-NA-2752024-12-19. Service bulletin. POWER TRAIN; WHEELS; AIR BAGS. This service bulletin provides repair information to correct customer concerns of Wheel Lock Up, ABS Event, Loud Bang and a Flashing “D” on Driver Information Center (DIC) when Lightly or Moderately Accelerating Forcing an 8-7 or 8-6 Downshift.
08-07-30-035I2024-12-19. Service bulletin. POWER TRAIN. This service bulletin provides information on the harmful effects of ethylene glycol in transmission fluid.
N242454441-022024-12-17. Service bulletin. POWER TRAIN. 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.This special coverage covers the condition described above for a period of 15 years or 150,000 miles (240,000km), 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 November 26, 2024, 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 November 26, 2024, 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 install a new control valve body. The repairs will be made at no charge to the customer.
N242454441-022024-12-13. Service bulletin. POWER TRAIN. 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. This special coverage covers the condition described above for a period of 15 years or 150,000 miles (240,000km), 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 November 26, 2024, 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 November 26, 2024, 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.
N242454441-012024-12-12. Service campaign. POWER TRAIN. 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. This special coverage covers the condition described above for a period of 15 years or 150,000 miles (240,000km), 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 November 26, 2024, 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 November 26, 2024, 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 install a new control valve body. The repairs will be made at no charge to the customer.
PIP60142024-12-05. Service bulletin. POWER TRAIN. This Preliminary information communicates for Technicians installing a Service Replacement Transmission Assembly to contact Technical Assistance to make sure unit is not suspect of a snap ring concern prior to installation.
04-06-01-029K2024-12-04. Service bulletin. POWER TRAIN; STEERING; ENGINE. This informational bulletin explains Unscheduled Supplemental Services and the importance of GM Simplified Maintenance Schedules.
N2424544412024-11-27. Service bulletin. POWER TRAIN. 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. This special coverage covers the condition described above for a period of 15 years or 150,000 miles (240,000km), 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 November 26, 2024, 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 November 26, 2024, 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 install a new control valve body. The repairs will be made at no charge to the customer.
20-NA-1382024-11-05. Service bulletin. POWER TRAIN; ENGINE. This bulletin provides information on Policies Applicable to All U.S. Dealers for Engine and Transmission Assembly Replacement Under Warranty, Policy or Customer Enthusiasm and information on Submission of Warranty Transaction in Global Warranty Management.
21-NA-2752024-10-30. Service bulletin. WHEELS; SERVICE BRAKES; POWER TRAIN. This service bulletin provides repair information to correct customer concerns of Rear Wheel Lock Up, ABS Event, Loud Bang and a Flashing “D” on Driver Information Center (DIC) when Lightly or Moderately Accelerating Forcing an 8-7 or 8-6 Downshift.
21-NA-1202024-10-24. Service bulletin. POWER TRAIN. This service bulletin provides a Diagnostic Tip for Noise, Vibration, and/or Harshness Issues/Clunk Noise Heard During Coast Down Event after the transfer case was removed from the transmission and reinstalled during a recent repair.

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