Vehicle report
Technical service bulletins are instructions a manufacturer sent its dealers about a known fault. They are not recalls and the work is usually not free, but they are the clearest signal of a problem the manufacturer already knows about.
WSB-42-05
WESTERN STAR: AN ISSUE WITH THERMAL OVERLOAD ON BENDIX AIR DISC BRAKES WHERE ABS SENSOR WIRES MELTS, BRAKE ACTUATOR FAILS TO PROPERLY OPERATE DUE TO VENT HOLE IN BOTTOM NOT OPENING, CALIPERS COATED WITH RED OR BRIGHT ORANGE DUST AND TAPPED AND/OR GUIDE PIN BOOTS MELTED OR OTHERWISE SHOWS HEAT DAMAGE. MODELS CONSTELLATION, 4700, 4800, 4900, 5900 AND 6900. NO MODEL YEARS LISTED. *PE
WSB-42-6
WESTERN STAR: WHEN APPLYING THE BRAKES, SOME TRUCKS WILL EXPERIENCE SEVERE SHAKING OR SHIMMYING. MODELS CONSTELLATION, 4700, 4800, 4900, 6900 AND 5900. NO MODEL YEARS LISTED. *PE UPDATED 11/1/12. *PE
SB-49-12
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
Complaint counts are reports filed with NHTSA, not failure rates. A common model collects more of them than a rare one that breaks more often.