Service bulletins for the 2021 Western Star 4900
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.
117 on file from NHTSA, as of 2026-10-19.
By type
By component
Only bulletins with component: Glass, wipers and mirrors are shown. Show all
| SBW83-030 | 2022-07-02. Service bulletin. VISIBILITY. Updated Western Star Service Bulletin for HVAC Actuator Replacement |
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| SBW83-030 | 2022-06-04. Service bulletin. VISIBILITY. Western Star Service Bulletin for HVAC Actuator Replacement. The wiring harness of the actuator of the fresh air recirculation door on Western Star vehicles equipped with Red Dot HVAC systems should be inspected for signs of water intrusion and corrosion. |
| CALWS83-001REV | 2022-01-04. Service bulletin. VISIBILITY. HVAC Actuator Wiring Harness. Revision History: Service kit part number changed from RDH RD5 17147 0 to WWS RD-3-9069-0 on 12/9/21. The wiring harness of the actuator of the fresh air recirculation door, shown in Fig. 1, on Western Star vehicles equipped with Red Dot HVAC systems should be inspected for signs of water intrusion and corrosion. |
| ICI21-030 | 2021-11-03. Service bulletin. VISIBILITY. SF626 Western Star Window Replacement Inspection Notification. This letter is to inform you that Field Service Campaign SF626 Western Star Window Replacement Inspection Notification campaign was released. |
| CALWS83-001 | 2021-09-29. Service bulletin. ELECTRICAL SYSTEM; VISIBILITY. Customer Advisory Letter for HVAC Actuator Wiring Harness. The wiring harness of the actuator of the fresh air recirculation door, shown in Fig. 1, on Western Star vehicles equipped with Red Dot HVAC systems should be inspected for signs of water intrusion and corrosion. |
| TechTalk7901 | 2020-12-03. Service bulletin. ELECTRICAL SYSTEM:WIRING; VISIBILITY. Tech Talk discussion on Delayed Wiper Response. |
| TechTalk7774 | 2020-11-03. Service bulletin. VISIBILITY; EQUIPMENT ADAPTIVE/MOBILITY; EQUIPMENT. Tech Talk discussion on SS 1034711 HADLEY MIRROR |
| SS1034711 | 2020-05-23. Service bulletin. VISIBILITY:REARVIEW MIRRORS/DEVICES. Service Solution for Hadley Upper Mirror Glass Vibration. The following suggestions are not guaranteed to eliminate or fix the Hadley mirror vibration concern. We have had mixed results in field-testing. In some cases, these solutions eliminate or reduce the vibration and in others, it does not seem to make a difference. DTNA continues to work on a permanent solution to this concern. |
| SS1034615 | 2020-01-28. Service bulletin. VISIBILITY; EQUIPMENT ADAPTIVE/MOBILITY. Service Solution for Western Star Velvac Door Mirror Seal Curling. The rubber that is rolling back is actually a rubber tape. Originally, the mirrors did not have this tape. Velvac added the tape to address some whistling complaints from customers. |
The summaries are NHTSA's. Each bulletin's page links NHTSA's copy of the manufacturer's document.