NHTSA service bulletin

NHTSA Service Bulletin 10044353: 1994-2013 Western Star 4700

Official manufacturer communication context for 1994-2013 Western Star 4700, with affected products, buyer checks and links into Carchieve recall, problem and VIN research.

NHTSA service bulletin 10044353 summary graphic for 1994-2013 Western Star 4700
10044353NHTSA document ID
Manufacturer communicationcommunication type
15affected product rows
80/100quality score

Reviewed June 2026 from NHTSA manufacturer communication and service bulletin records. Carchieve is independent and not affiliated with any vehicle manufacturer or government agency.

Quick answer

WESTERN STAR: AROUND THE DIESEL EXHAUST FLUID (DEF) AN EXCESSIVE AMOUNT OF CRYSTAL OR POWDER BUILT UP INDICATES A LEAK CAUSED BY EVAPORATION OF DEF EXPOSED TO AIR AND/OR DAMPNESS. *PE

What this bulletin may mean before buying

Treat this as service research, not a verdict on one car. Before you buy, compare this communication with official recall campaigns, model-level owner complaint patterns, and the exact vehicle’s VIN-decoded specifications. A bulletin can help you ask a seller or dealer sharper questions about software updates, known repairs, warranty extensions and service history.

Affected products listed in this communication

MakeModelModel yearsBuyer note
Western Star47002012, 2013Ask for service records and run the exact VIN before purchase.
Western Star48001994-2002Ask for service records and run the exact VIN before purchase.
Western Star48fxmodel years not specifiedAsk for service records and run the exact VIN before purchase.
Western Star49001994-2013Ask for service records and run the exact VIN before purchase.
Western Star4900 Sa2002-2011Ask for service records and run the exact VIN before purchase.
Western Star4900ex2003, 2004, 2006, 2007Ask for service records and run the exact VIN before purchase.
Western Star4900fa2000, 2003, 2004Ask for service records and run the exact VIN before purchase.
Western Star4900sa2003, 2004Ask for service records and run the exact VIN before purchase.
Western Star58001997-2002Ask for service records and run the exact VIN before purchase.
Western Star59001994, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003Ask for service records and run the exact VIN before purchase.
Western Star5900 Heavy Dutymodel years not specifiedAsk for service records and run the exact VIN before purchase.
Western Star5900ssmodel years not specifiedAsk for service records and run the exact VIN before purchase.
Western Star59ssmodel years not specifiedAsk for service records and run the exact VIN before purchase.
Western Star69001994-2013Ask for service records and run the exact VIN before purchase.
Western StarConstellation1995, 1996, 1997, 1998, 1999, 2001, 2009, 2010, 2011, 2012Ask for service records and run the exact VIN before purchase.

Buyer checklist

  1. Run the 17-character VIN and confirm the year, make, model, engine and equipment match the listing.
  2. Check recall campaign pages for safety actions that may require dealer repair.
  3. Compare this bulletin with common problem pages for the same model and component area.
  4. Ask the seller or dealer whether the bulletin procedure, update or inspection has already been completed.
  5. Use the used-car buying checklist and get an independent inspection.

Frequently asked questions

What is NHTSA service bulletin 10044353?

WESTERN STAR: AROUND THE DIESEL EXHAUST FLUID (DEF) AN EXCESSIVE AMOUNT OF CRYSTAL OR POWDER BUILT UP INDICATES A LEAK CAUSED BY EVAPORATION OF DEF EXPOSED TO AIR AND/OR DAMPNESS. *PE

Is a service bulletin the same as a recall?

No. A recall is a safety campaign with a required remedy for affected VINs. A service bulletin or manufacturer communication usually describes diagnostic, repair, software, warranty or service information.

How should a used-car buyer use this bulletin?

Use it as a research signal. Compare it with recalls, owner complaints, service records, a VIN report and an independent inspection before buying.

Check the exact VIN before you buy

Model-level pages show public safety patterns. A full VIN report helps confirm the exact vehicle, decoded specs, recall applicability and buyer checks.

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