Service bulletins for the 2020 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.
156 on file from NHTSA, as of 2026-10-19.
By type
By component
Only bulletins with component: Engine are shown. Show all
| CXA_10_25_Conmet Oil Pan | 2025-11-05. Other. ENGINE. CX Advocate for ConMet Oil Pan Insert Additional Issues |
|---|---|
| CXA 3_25_NOx | 2025-04-02. Other. ENGINE. CX Advocate for NOx conversion low faults |
| CXA 2_25_NOx | 2025-03-04. Other. ENGINE. CX Advocate for NOx conversion low faults |
| TSB01-001-DDC | 2025-03-04. Service bulletin. ENGINE. Technical Service Bulletin for GHG17 and Newer DD Platform Heavy Duty Oil Pan Drain Plug Inserts |
| CXA 1_16_NOx | 2025-01-29. Other. ENGINE. CX Advocate for NOx conversion low faults |
| CXA 1_16_CARB Truck Chec | 2025-01-29. Other. ENGINE. CX Advocate for CARB tightening the Readiness Criteria applied to On-Board Diagnostic (OBD) test submissions for the Clean Truck Check. |
| CXA 11_21_CARB Truck Chec | 2024-12-04. Other. ENGINE. CX Advocate for CARB tightening the Readiness Criteria applied to On-Board Diagnostic (OBD) test submissions for the Clean Truck Check. |
| WI24-019 | 2024-12-04. Warranty extension. ENGINE. Warranty Information letter for Detroit Line or Line Seal, High Pressure Fuel Injector Standard Repair Time Updates |
| CXA_10_17_CARB Truck Chec | 2024-11-07. Other. ENGINE. CX Advocate for CARB tightening the Readiness Criteria applied to On-Board Diagnostic (OBD) test submissions for the Clean Truck Check. |
| SS1023366-Detroit | 2024-11-06. Other. ENGINE. Service Solution for Detroit Successful Regen Reference for GHG17 DD Engines |
| SS1023366-Detroit | 2024-10-04. Other. ENGINE. Service Solution for Detroit Successful Regen Reference for GHG17 DD Engines |
| CXA 8_24_Conmet Oil Pan | 2024-09-07. Other. ENGINE. CX Advocate for ConMet Oil Pan Insert Additional Failures |
| ICI24-031 | 2024-09-07. Other. ENGINE. Important Campaign Information letter for DDC D23M3 - Campaign Reactivated and Extended. Field Service Campaign D23M3 - GHG17 DETROITTM DD16® Vibration Damper Replacement has been extended for an additional 6 months. |
| CXA 7_24_NOx | 2024-08-02. Other. ENGINE. CX Advocate for NOx conversion low faults. Update to CXA 6_24_NOx submission. |
| CXA 7_24_Conmet Oil Pan | 2024-08-02. Other. ENGINE. CX Advocate for ConMet Oil Pan Insert Additional Failures |
| CXA 06_24_NOx | 2024-07-09. Other. ENGINE. CX Advocate communication for NOx conversion low faults |
| VSWP Customer Letter | 2024-06-22. Other. ENGINE. Customer letter regarding variable speed water pump. |
| SS763-WST | 2024-06-05. Other. ENGINE. Service Solution for DEF Pump Wiring for Cummins CM2450 Engine Controller |
| SS3144-FTL | 2024-05-07. Service bulletin. ENGINE AND ENGINE COOLING. Service Solution for DEF Pump Wiring for Cummins CM2450 Engine Controller |
| ICI24-006 | 2024-03-06. Service bulletin. ENGINE AND ENGINE COOLING. Important Campaign Information letter for FL974 - Revised Bulletin & Population |
| FL974 | 2024-03-06. Service bulletin. ENGINE AND ENGINE COOLING. Revised Emissions Recall: Cummins DEF Sensor Shortage. REVISION: Some vehicles formerly in Group F have been moved to Group G and have been assigned a new part number as specified in Table 1. An SRT for 'Calibration Code Only: Update or Confirm' has been added, as shown in Table 2, to be used when a new DEF header is not required. There have been some other minor changes to the work instructions and SRT times. |
| FL974 | 2024-02-06. Service bulletin. ENGINE AND ENGINE COOLING. Emissions Recall: Cummins DEF Sensor Shortage |
| SBW49-020 | 2022-03-03. Service bulletin. ENGINE AND ENGINE COOLING. Western Star Service Bulletin for DEF Connector Reinforcement Caps |
| WI21-009 | 2021-04-24. Service bulletin. ENGINE AND ENGINE COOLING. Warranty Information letter announcing that DTNA is increasing the Standard Diagnostic Times (SDTs) shown. The updated after treatment system (ATS) diesel exhaust fluid (DEF) pump times will be applied to repair orders opened on or after April 12, 2021. |
| WI21-004 | 2021-03-02. Service bulletin. POWER TRAIN; ENGINE AND ENGINE COOLING. Warranty Information Letter for Detroit Resources: Exploded View DD Platform and DT12 Posters. Detroit's TechComm team created visual aids for the network and released exploded view posters for DD platform engines. In early 2021, Detroit added multiple DT12 posters. |
The summaries are NHTSA's. Each bulletin's page links NHTSA's copy of the manufacturer's document.