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Service bulletins for the 2021 Chevrolet Blazer

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.

814 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
PIP5621C2022-10-17. Service bulletin. POWER TRAIN:AUTOMATIC TRANSMISSION:CONTROL MODULE (TCM/PCM/TECM); POWER TRAIN. This Preliminary information communicates to the dealer technician that TAC recommends the utilization of the GDS2 software to aid in diagnosing automatic transmission concerns. TAC is requesting the GDS2 session logs be sent in before the dealer contacts TAC.
PIT5847F2022-10-17. Service bulletin. POWER TRAIN; FUEL SYSTEM, GASOLINE; AIR BAGS; LANE DEPARTURE. This Preliminary information communicates that a vehicle may come into the dealer with various concerns which may include a service engine light or various warning messages on the DIC. The technician is instructed to inspect a wiring harness for chaffing on a bracket which is located beneath the battery tray, at a transmission stud and at the transmission oil cooler line bracket. If damage to the harness is found the technician is instructed to repair the damaged wiring and secure the harness away from the bracket so that future damage to the harness will be eliminated.
PIP5640A2022-10-17. Service bulletin. POWER TRAIN. This Preliminary Information communication provides information to the technician to not remove the torque converter bolts and start the engine as this may cause damage to the torque converter of the crankshaft on vehicles equipped with an automatic transmission.
15-00-89-004E2022-10-11. Service bulletin. POWER TRAIN; SUSPENSION; ENGINE AND ENGINE COOLING; SERVICE BRAKES, HYDRAULIC; STEERING. This service bulletin provides technicians with updated information to help identify the differences between what is considered a fluid leak, and what is considered fluid seepage.
06-00-89-031H2022-10-11. Service bulletin. POWER TRAIN; ENGINE AND ENGINE COOLING. This service bulletin provides information on OEM and Remanufactured Engine and Automatic Transmission/Transaxle Identification.
22-NA-1812022-09-19. Service bulletin. POWER TRAIN. This diagnostic tip advises the tech not to separate the flexplate from the torque convertor or damage my occur if the engine is started while diagnosing for noise from the engine or transmission.
21-NA-1812022-09-08. Service bulletin. POWER TRAIN. This service bulletin provides 9th gear operation information to respond to customers that may comment on transmission shift operation.
21-NA-1692022-08-16. Service bulletin. POWER TRAIN. This service bulletin provides diagnostic information/procedures to aid the service technician in diagnosing 9T45/50/60 automatic transmissions with low mileage and DTCs current or history related to the control solenoids and valves.
20-NA-1362022-08-16. Service bulletin. POWER TRAIN. This informational bulletin describes/outlines the process for the 9T65 Automatic Transmission Replacement Pilot Program (U.S. Only).
PIT5847E2022-08-15. Service bulletin. POWER TRAIN; POWER TRAIN:AUTOMATIC TRANSMISSION:COOLER/RADIATOR:HOSES AND FITTINGS. This Preliminary information communicates that a vehicle may come into the dealer with various concerns which may include a service engine light or various warning messages on the DIC. The technician is instructed to inspect a wiring harness for chaffing on a bracket which is located beneath the battery tray, at a transmission stud and at the transmission oil cooler line bracket. If damage to the harness is found the technician is instructed to repair the damaged wiring and secure the harness away from the bracket so that future damage to the harness will be eliminated.
22-NA-1072022-08-03. Service bulletin. ELECTRICAL SYSTEM:IGNITION; POWER TRAIN. This service bulletin provides repair information to correct a customer concern of a Service AWD Message in DIC at Ignition On with DTC C056D Set.
20-NA-1362022-08-03. Service bulletin. POWER TRAIN. This informational bulletin describes/outlines the process for the 9T65 Automatic Transmission Replacement Pilot Program (U.S. Only).
PIT5847D2022-06-13. Service bulletin. ELECTRICAL SYSTEM; ENGINE AND ENGINE COOLING; POWER TRAIN. This Preliminary information communicates that a vehicle may come into the dealer with various concerns which may include a service engine light or various warning messages on the DIC. The technician is instructed to inspect a wiring harness for chaffing on a bracket which is located beneath the battery tray, at a transmission stud and at the transmission oil cooler line bracket. If damage to the harness is found the technician is instructed to repair the damaged wiring and secure the harness away from the bracket so that future damage to the harness will be eliminated.
22-NA-1072022-06-04. Service bulletin. ELECTRICAL SYSTEM; POWER TRAIN:AUTOMATIC TRANSMISSION. This service bulletin provides repair information to correct a customer concern of a Service AWD Message in DIC at Ignition On with DTC C056D Set.
PIE06992022-06-01. Service bulletin. POWER TRAIN. 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 AWD Lamp illuminated on the driver information center (DIC).
21-NA-1812022-04-21. Service bulletin. POWER TRAIN; EQUIPMENT. This service bulletin provides 9th gear operation information to respond to customers that may comment on transmission shift operation.
21-NA-1692022-04-15. Service bulletin. POWER TRAIN. This service bulletin provides diagnostic information/procedures to aid the service technician in diagnosing 9T45/50/60 automatic transmissions with low mileage and DTCs current or history related to the control solenoids and valves.
21NA1812022-02-14. Service bulletin. POWER TRAIN. This service bulletin provides 9th gear operation information to respond to customers that may comment on transmission shift operation.
21NA1692021-12-27. Service bulletin. POWER TRAIN:AUTOMATIC TRANSMISSION. This service bulletin provides diagnostic information/procedures to aid the service technician in diagnosing 9T45/50/60 automatic transmissions with low mileage and DTCs current or history related to the control solenoids and valves.
20NA1362021-12-27. Service bulletin. EQUIPMENT; POWER TRAIN. This informational bulletin describes/outlines the process for the 9T65 Automatic Transmission Replacement Pilot Program (U.S. Only).
20NA1362021-12-20. Service bulletin. POWER TRAIN. This informational bulletin describes/outlines the process for the 9T65 Automatic Transmission Replacement Pilot Program (U.S. Only).
PIP5608H2021-10-25. Service bulletin. POWER TRAIN. This Preliminary information communicates to perform a transmission fluid drain and fill to correct a TCC shudder concern.
PIP5608G2021-09-13. Service bulletin. POWER TRAIN. This Preliminary information communicates to perform a transmission fluid drain and fill to correct a TCC shudder concern.
PIP5608F2021-09-13. Service bulletin. POWER TRAIN. This Preliminary information communicates to perform a transmission fluid drain and fill to correct a TCC shudder concern.
PIC5650J2021-09-13. Service bulletin. POWER TRAIN; AIR BAGS. This Preliminary Information communication provides information to the technician about vehicles that have an intermittent no crank, no start, or start stall concern with the security light coming on. Technician may find Diagnostic Trouble Codes B3055, B3060, and/or B3935. Technician should not replace any parts for this concern. If unable to duplicate the concern ask if the customer uses any Radio Frequency Identification Devices when the concern is present. Dealer should also direct their customers to the appropriate section in the Owner manuals that references that the device complies.

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