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Service bulletins for the 2020 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.

854 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
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.
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.
PIP5708B2021-09-13. Service bulletin. POWER TRAIN; BACK OVER PREVENTION; ELECTRICAL SYSTEM. This Preliminary information communicates to the technician the vehicle concern of starter flex plate having broken teeth. This can create a noise during starting or may even have the starter spin but not crank over the engine. The document directs the technician to replace the flex plate and inspect the starter pinion drive teeth and replace starter assembly as needed.
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.
990420002L2021-08-09. Service bulletin. POWER TRAIN:MANUAL TRANSMISSION; POWER TRAIN:AUTOMATIC TRANSMISSION; EQUIPMENT. This service bulletin provides information on Driveline Clunk Noise and what is acceptable and what is considered normal operation.
080730035E2021-08-09. Service bulletin. EQUIPMENT; EQUIPMENT ADAPTIVE/MOBILITY; POWER TRAIN. This bulletin provides information on the harmful effects of water or ethylene glycol in transmission fluid.
20NA1362021-07-19. Service bulletin. POWER TRAIN. This informational bulletin describes/outlines the process for the 9T65 Automatic Transmission Replacement Pilot Program (U.S. Only).
20NA1362021-07-06. Service bulletin. POWER TRAIN. This informational bulletin describes/outlines the process for the 9T65 Automatic Transmission Replacement Pilot Program (U.S. Only).
PIP5720A2021-06-14. Service bulletin. POWER TRAIN. This Preliminary information communicates that a possible trans fluid leak found may only be residual fluid that was left during the assembly process with no repairs needed if no dye is detected after cleaning and re-evaluation.
16NA3382021-05-24. Service bulletin. POWER TRAIN. This Warranty Admin service bulletin provides guidelines for Dealers Not Required and for Dealers Required to Contact the PQC for engine or transmission assembly replacement and explains the PQC process, GWM Transaction submission, vehicle service record retention and proper handling of assembly returns for Canadian Dealers only.
PIP58022021-05-17. Service bulletin. POWER TRAIN. This Preliminary information communicates diagnostic assistance for DTC's P219A and P219B.
20NA1382021-05-03. Service bulletin. ENGINE AND ENGINE COOLING; POWER TRAIN. 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.
PIP5712B2021-04-19. 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.
150089004C2021-03-08. Service bulletin. SUSPENSION:FRONT:MACPHERSON STRUT; SUSPENSION:FRONT:SHOCK ABSORBER; POWER TRAIN:AUTOMATIC TRANSMISSION:FLUID/LUBRICANT. 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.
16NA0192021-02-22. Service bulletin. POWER TRAIN. This informational bulletin provides information on Transmission Adaptive Functions and Correcting Low Mileage Harsh Shifts, Slips, or Flares.

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