Service bulletins for the 2021 Chevrolet 4500HD
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.
318 on file from NHTSA, as of 2026-10-19.
By type
By component
By trouble code
By topic
Only bulletins with component: Electrical system are shown. Show all
| 22-NA-115 | 2022-06-06. Service bulletin. ENGINE AND ENGINE COOLING; ELECTRICAL SYSTEM. This service bulletin provides information for U.S. dealers ONLY to refer to the Battery Maintenance Report to identify vehicles in dealer inventory that require attention. |
|---|---|
| 22NA012 | 2022-05-31. Service bulletin. ELECTRICAL SYSTEM:ADAS:PARKING ASSIST:SENSORS. This service bulletin provides information for dealers/technicians on Stone Chip/Membrane Damage, Broken Connector and/or Sensor Retaining Tabs, and/or Paint Damage of Park Assist Sensors. |
| 21-NA-115 | 2022-04-06. Service bulletin. ENGINE AND ENGINE COOLING; EQUIPMENT; ELECTRICAL SYSTEM. This informational bulletin provides information for dealers/technicians on Available ECM Calibration to Activate High Idle Mode for Fleet Vehicles. |
| 20NA132 | 2021-12-20. Service bulletin. ELECTRICAL SYSTEM:12V/24V/48V BATTERY. This warranty administration bulletin provides policy information on the requirements for battery testing and warranty replacements. |
| 21NA124 | 2021-07-06. Service bulletin. ELECTRICAL SYSTEM. This service bulletin provides diagnostic tips/steps on testing for possible EVAP leaks in the system to correct a customer concern of an MIL Illuminated with DTCs P0442 and/or P0455 Set. |
The summaries are NHTSA's. Each bulletin's page links NHTSA's copy of the manufacturer's document.