2002 Workhorse W20 recalls and problems

THE EA WAS OPENED TO GAIN A TECHNICAL UNDERSTANDING OF THE CAUSES FOR ONE OR MORE DISC BRAKE CALIPERS ON A SUBJECT VEHICLE TO SUFFER SEVERE OVERHEATING. THE OVERHEATING CAUSED BRAKE DRAG, MELTING ABS SENSORS, SMOKING, BRAKE LINING FIRES, AND IN SOME CASES BOILING BRAKE FLUID RESULTING IN DIMINISHED STOPPING CAPABILITY.BASED ON TESTING, WARRANTY AND COMPLAINT DATA ANALYSIS, FIELD TRIPS AND INTERVIEWS WITH OWNERS, MECHANICS AND SERVICE MANAGERS, ODI BELIEVES THE LIKELY CAUSE OF THE ALLEGED DEFECT IS WATER SWELL OF THE PHENOLIC CALIPER PISTON AND SUBSEQUENT FAILURE OF THE PISTON TO FULLY RETURN AFTER THE PEDAL IS RELEASED.A TECHNICAL REPORT IS ATTACHED WITH FULL DETAILS.

ON JUNE 25, 2007, THE OFFICE OF DEFECTS INVESTIGATION (ODI) OPENED A PRELIMINARY EVALUATION TO INVESTIGATE ALLEGED OVERHEATING DISC BRAKE CALIPERS AND POOR BRAKE PERFORMANCE IN MODEL YEAR (MY) 2000-2005 WORKHORSE CHASSIS RECREATIONAL VEHICLES.CURRENTLY ODI IS AWARE OF 651 SPECIFIC COMPLAINTS ON THE SUBJECT VEHICLES (ODI AND WORKHORSE COMPLAINT POPULATION).ODI ANALYSIS OF THE WARRANTY AND COMPLAINT DATA FURNISHED BY WORKHORSE ON SEPTEMBER 11, 2007, IN RESPONSE TO ODI'S INFORMATION REQUEST INDICATES A DRAMATIC DROP IN BRAKE RELATED COMPLAINTS AFTER THE MAY 2004 BUILD DATE.AT THAT TIME, WORKHORSE INCORPORATED INTO PRODUCTION ZERK FITTINGS AND GREASING OF THE BRAKE MASTER CYLINDER'S BELL CRANK LINKAGE.ODI IS ALSO AWARE OF 3,782 UNIQUE WARRANTY COUNTS RELATED TO THE ALLEGED DEFECT IN THE SUBJECT POPULATION.A REVIEW OF THE WARRANTY CLAIMS REVEALS THAT OF THE CLAIMS FILED, ONLY 88 WERE SUBMITTED ON VEHICLES PRODUCED AFTER THE MAY 2004 PRODUCTION LINE CHANGE (ADDITION OF ZERK FITTINGS).ODI INTENDS TO OBTAIN AN UNDERSTANDING OF WHY THERE ARE SEEMINGLY SIGNIFICANT DIFFERENCES IN THE COMPLAINT DATA AND WARRANTY CLAIMS BEFORE AND AFTER THE MAY 2004 DESIGN CHANGE AND THE SAFETY CONSEQUENCES OF THE PRE-CHANGE DESIGN. THIS INVESTIGATION HAS BEEN UPGRADED TO AN ENGINEERING ANALYSIS (EA07-016) FOR FURTHER INVESTIGATION.

THIS INVESTIGATION WAS DERIVED FROM INFORMATION GATHERED DURING PE02-046, BOSCH DISC BRAKE CALIPERS.THIS INVESTIGATION FOCUSED ON THE VEHICLE MANUFACTURER, NEWMAR.SUBJECT VEHICLES WERE THOSE BUILT WITH A HYDRAULIC BRAKE SYSTEM INCORPORATING THE BOSCH ZERO OFFSET PIN SLIDE (ZOPS) CALIPERS.ODI'SCONCERN WASEXCESSIVE WHEEL END HEAT, POSSIBLY RESULTING IN A WHEEL END FIRE.DURING THE INVESTIGATION, ODI DISCOVERED TWO SPECIFIC NEWMAR VEHICLE MODELS, THOSE BUILT ON NEWMAR CHASSIS AND THOSE BUILT ON A WORKHORSE CHASSIS. AS A RESULT OF THE AGENY'S INVESTIGATION INTO THIS MATTER, ALL NEWMAROWNERS WILL BE NOTIFIED (04V-019) AND THE REMEDY WILL BE APPLIED TO THEIR VEHICLES. SOME NEWMAR VEHICLES (1,795) BUILT ON THE WORKHORSE CHASSIS ARE BEING RECALLED BY WORKHORSE (04V-084).THIS INVESTIGATION IS CLOSED.FURTHER DETAILS ARE PROVIDED ON PAGES 2, 3, AND 4.COPIES OF BOTH SAFETY RECALLS ARE ATTACHED.