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Service bulletins for the 2021 Chevrolet 4500XD

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.

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

By type

By component

By trouble code

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Only bulletins with component: Electrical system are shown. Show all

Bulletins, newest first
22-NA-1152022-06-06. 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.
21-NA-1152022-04-06. 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.
21NA0682021-05-10. Service bulletin. ELECTRICAL SYSTEM:IGNITION:ANTI-THEFT:IMMOBILIZER/PROXIMITY:KEY/SENDER. This warranty administration bulletin provides policy information requirements applicable to key fob replacement under the New Vehicle Limited Warranty or under a Replacement Parts Warranty on 2021 and newer model year vehicles with RPO ATH (U.S. Only).
21NA0612021-05-10. Service bulletin. ELECTRICAL SYSTEM:IGNITION:ANTI-THEFT:IMMOBILIZER/PROXIMITY:KEY/SENDER. This service bulletin provides information for dealers on Using EL-52545 When Diagnosing PEPs Transmitter Key Fobs (North America ONLY).
20NA1322021-05-03. Service bulletin. ELECTRICAL SYSTEM. This warranty administration bulletin provides policy information on the requirements for battery testing and warranty replacements.

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