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Service bulletins for the 2021 Western Star 5700

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.

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

Warranty extensions
WI24-0192024-12-04. ENGINE. Warranty Information letter for Detroit Line or Line Seal, High Pressure Fuel Injector Standard Repair Time Updates

A warranty extension may pay for a repair after the basic warranty has ended. Read the document for which vehicles and which repair it covers.

By type

By component

Bulletins, newest first
PB-47-900-WST2026-07-06. Service bulletin. FUEL/PROPULSION SYSTEM. Parts Bulletin for Fluorosilicone Fuel Tank Cap Seals
CXA 03_26_Surge Tank2026-04-02. Other. ENGINE. CX Advocate for discolored coolant surge tanks (24CSA-20)
TSB-32-020-WST2026-03-27. Service bulletin. SUSPENSION. Technical Service Bulletin for TufTrac M12 Bolts
CXA_10_25_Tech Questions2025-11-05. Other. ELECTRICAL SYSTEM; POWER TRAIN. CX Advocate for technical questions/issues raised
CXA_10_25_Conmet Oil Pan2025-11-05. Other. ENGINE. CX Advocate for ConMet Oil Pan Insert Additional Issues
CXA_9_25_Tech Questions2025-10-03. Other. POWER TRAIN; ENGINE. CX Advocate for technical questions/issues raised
CXA_8_25_Tech Questions2025-09-02. Other. POWER TRAIN; ENGINE; UNKNOWN OR OTHER. CX Advocate for technical questions/issues raised
24CSA-19Rev2025-09-02. Other. ENGINE. Revised Customer Service Annoucement for No Trouble Found Heavy Duty Engine Product (HDEP) Oil Separator Leaks
PB33-005-WST2025-07-08. Service bulletin. STEERING. Parts Bulletin for Tie Rod Assembly Part Breakdown
TSB26-008-WST2025-05-02. Service bulletin. POWER TRAIN. Service Solution for DT12 Oil Plug Ports
CXA 3_25_NOx2025-04-02. Other. ENGINE. CX Advocate for NOx conversion low faults
CXA 2_25_NOx2025-03-04. Other. ENGINE. CX Advocate for NOx conversion low faults
TSB01-001-DDC2025-03-04. Service bulletin. ENGINE. Technical Service Bulletin for GHG17 and Newer DD Platform Heavy Duty Oil Pan Drain Plug Inserts
SS778-WST2025-01-29. Other. STEERING. Service Solution for Power Steering Reservoir Fill Cap Venting
CXA 1_16_NOx2025-01-29. Other. ENGINE. CX Advocate for NOx conversion low faults
WI24-0192024-12-04. Warranty extension. ENGINE. Warranty Information letter for Detroit Line or Line Seal, High Pressure Fuel Injector Standard Repair Time Updates
SS1023366-Detroit2024-11-06. Other. ENGINE. Service Solution for Detroit Successful Regen Reference for GHG17 DD Engines
24CSA-202024-11-06. Service bulletin. ENGINE. Customer Service Annoucement for Discolored Coolant Surge Tank on Heavy Duty Engine Product (HDEP)
24CSA-192024-11-06. Other. ENGINE. Customer Service Annoucement for Heavy-Duty Engine Product (HDEP) Oil Separator Leaks
SS1023366-Detroit2024-10-04. Other. ENGINE. Service Solution for Detroit Successful Regen Reference for GHG17 DD Engines
CXA 8_24_Conmet Oil Pan2024-09-07. Other. ENGINE. CX Advocate for ConMet Oil Pan Insert Additional Failures
CXA 7_24_NOx2024-08-02. Other. ENGINE. CX Advocate for NOx conversion low faults. Update to CXA 6_24_NOx submission.
CXA 7_24_Conmet Oil Pan2024-08-02. Other. ENGINE. CX Advocate for ConMet Oil Pan Insert Additional Failures
CXA 06_24_Clutch Bolts2024-07-09. Other. POWER TRAIN. CX Advocate communication for clutch bolts
CXA 06_24_NOx2024-07-09. Other. ENGINE. CX Advocate communication for NOx conversion low faults

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