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Service bulletins for the 2021 Chevrolet Express

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.

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

By type

By component

By trouble code

By topic

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

Bulletins, newest first
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.
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
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.
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.
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.
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.
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.
08-07-30-026I2024-10-24. Service bulletin. POWER TRAIN. This service bulletin provides information on some vehicles that may rock or move slightly forward or rearward while in Park at start up after cold soak. This condition may be accompanied by a clunk noise. This is a slight movement that is more often seen visually, rather than felt, when viewed from the outside and using the auto-start feature, if equipped.
23-NA-1422024-10-17. Service bulletin. POWER TRAIN. This technical bulletin provides a procedure for the techs to replace the forward check ball and separator plate if found the cause of the customers concern of No Forward Gear When Shifting from Park to Drive and/or Reverse to Drive.
PIP6000A2024-09-14. Service bulletin. POWER TRAIN. This Preliminary Information communication advises the technician on a parts restriction on the Generation I 8 speed rear wheel drive valve bodies.
PIP60002024-09-13. Service bulletin. POWER TRAIN. This Preliminary Information communication advises the technician on a parts restriction on the Generation I 8 speed rear wheel drive valve bodies.
PIP5996A2024-09-13. Service bulletin. POWER TRAIN. This Preliminary information communicates diagnostic information for vehicles with transmission noise.
PIP59962024-09-11. Service bulletin. POWER TRAIN. This Preliminary information communicates diagnostic information for vehicles with transmission noise
23-NA-1422024-08-16. Service bulletin. POWER TRAIN. This technical bulletin provides a procedure for the techs to replace the forward check ball and separator plate if found the cause of the customers concern of No Forward Gear When Shifting from Park to Drive and/or Reverse to Drive.
24-NA-1412024-08-15. Service bulletin. POWER TRAIN. GM is receiving damaged (cracked or broken) transmission cores returned to the reman facilities. The damage is being caused either in the removal process by the technician, or inadequate packaging or shipping. This bulletin advises the dealers to be more careful not to damage the transmissions during removal and to package the core properly for return.
PIP59772024-08-12. Service bulletin. POWER TRAIN. This Preliminary information communicates to the dealer technician that DTC P026D is under investigation.
23-NA-1422024-07-31. Service bulletin. POWER TRAIN. This technical bulletin provides a procedure for the techs to replace the forward check ball and separator plate if found the cause of the customers concern of No Forward Gear When Shifting from Park to Drive and/or Reverse to Drive.
99-04-20-002O2024-07-30. Service bulletin. POWER TRAIN. This service bulletin provides information on Driveline Clunk Noise and what is acceptable and what is considered normal operation.
16-NA-0192024-07-23. Service bulletin. POWER TRAIN. This service bulletin provides information on Transmission Adaptive Functions and Correcting Low Mileage Harsh Shifts, Slips, or Flares.
23-NA-1422024-06-18. Service bulletin. POWER TRAIN. This technical bulletin provides a procedure for the techs to replace the forward check ball and separator plate if found the cause of the customers concern of No Forward Gear When Shifting from Park to Drive and/or Reverse to Drive.
08-07-30-035H2024-06-07. Service bulletin. POWER TRAIN. This bulletin provides information on the harmful effects of water or ethylene glycol in transmission fluid.
15-00-89-004G2024-05-15. Service bulletin. ENGINE; SUSPENSION; POWER TRAIN. This service bulletin provides technicians with information to help identify the differences between what is considered a fluid leak, and what is considered fluid seepage.
N232428780-012024-04-17. Service bulletin. ENGINE AND ENGINE COOLING; POWER TRAIN. Certain vehicles may have a condition in which the transmission Control Valve Body Ball Check Valves can wear prematurely resulting in the possibility for them to become stuck or pass through the Control Valve Body Spacer Plate. The customer may not be able to shift into drive from park or reverse at the start of vehicle operation. Dealers are to replace the transmission Control Valve Body Spacer Plate package.

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