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Service bulletins for the 2020 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.

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

By type

By component

By trouble code

By topic

Bulletins, newest first
15NA0102020-03-02. Service bulletin. ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL. This informational bulletin provides information to dealership personnel for new vehicles with less than 1,000 miles that may not pass California smog inspection or smog inspection in other states.
100089009D2019-12-16. Service bulletin. EQUIPMENT; EQUIPMENT ADAPTIVE/MOBILITY. This informational bulletin provides information on key code security rules and information on GM keycode look-up applications.
080089014F2019-12-16. Service bulletin. EQUIPMENT; EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL. This informational bulletin provides information for dealers/technicians on Use of Dealer Case Management (DCM) and Being Prepared for Contacting U.S. Technical Assistance (TAC).
010842001M2019-12-16. Service bulletin. EQUIPMENT; EXTERIOR LIGHTING; EQUIPMENT ADAPTIVE/MOBILITY. This informational bulletin provides information for dealers/technicians on Exterior Lamp Condensation and Replacement Guidelines.
990420002K2019-11-25. Service bulletin. POWER TRAIN. This informational bulletin provides information on Driveline Clunk Noise and what is acceptable and what is considered normal operations.
010089010N2019-11-25. Service bulletin. EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL. This informational bulletin provides information on comebacks prevention information and using customer concern verification sheets (CCVS).
18NA3062019-11-25. Service bulletin. EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL. This Warranty Administration bulletin provides information for dealers/Service advisors on when and how to submit a Pre-Repair Authorization (PRA) (US dealers only).
17NA0502019-11-25. Service bulletin. EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL. This informational bulletin explains how a health report is required when doing repairs on LCF vehicles.

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