2001 Thomas Mvp Er

THE OFFICE OF DEFECTS INVESTIGATION OPENED THIS PRELIMINARY EVALUATIONAFTERBECOMING AWARE THAT FLEETS WERE HAVING HANDLE FAILURES ON THE REAR EMERGENCY DOOR EXIT.THE FAILURE RESULTED IN THE DOOR HANDLE SEPARATING FROM THEDOOR LATCH MECHANISM.WHEN THE HANDLE FAILS, THE REAR EMERGENCY EXIT DOOR CAN NOT BE OPENED FROM OUTSIDE THE BUS.THE FAILURE RESULTS FROM CORROSION OF THE EXTERIOR DOOR HANDLE AROUND THE SECURING ROLL PIN AND SQUARE DRIVE LATCH MECHANISM, CAUSING THE PROTECTIVE FINISH TO CHIP AND FLAKE.CONTINUED CORROSION WEAKENS THE HANDLE AND EVENTUALLY THE HANDLE MAY BREAK WHILE TRYING TO OPEN THE EXIT DOOR.ODI WAS CONCERNED THAT DURING AN EMERGENCY, A PERSON OUTSIDE OF THE BUS WOULD BREAK THE DOOR HANDLE WHILE TRYING TO OPEN THE EMERGENCY EXIT DOOR,POTENTIALLY DELAYING EVACUATION OF THE BUS.UNDER THE SAFETY RECALL, THE ALUMINUM HANDLES WILL BE REPLACED WITH A MORE ROBUST HANDLE.THE RECALL ACTION RESOLVES THE ISSUES RAISED BY THIS INVESTIGATION. ACCORDINGLY, THIS INVESTIGATION IS CLOSED.

THE OFFICE OF DEFECTS INVESTIGATION (ODI) OPENED THIS INVESTIGATION AFTER BECOMING AWARE OF TWO SCHOOL BUS FIRES THAT STARTED IN THE SIDE MOUNTED ELECTRICAL FUSE PANEL ON A PAIR OF THOMAS BUILT SCHOOL BUSES.THEFLEET OWNER HAD REPORTED THE BUS INTERIORS FILLED WITH SMOKE, CERTAIN ELECTRICAL DEVICES BECAME INOPERATIVE, AND THE BUSES STALLED. THE TWO BUSES INVOLVED IN THE FIRE INCIDENTS HAVE CONSECUTIVE VIN NUMBERS AND THE FIRES WERE SIMILAR, BUT NOT IDENTICAL TO A PREVIOUS RECALL (06V-136) CONDUCTED BY THOMAS BUILT.THESE BUSES WERE NOT INCLUDED IN THE PRIOR RECALL, WHICH INVOLVED A DEFECTIVE POWER DISTRIBUTION MODULE (PDM).AFTER FURTHER TECHNICAL EVALUATION, FREIGHTLINER DECIDED THEY WOULD CONDUCT A SAFETY RECALL TO CORRECT DEFICIENCIES IN THEPREVIOUS RECALL AND ALSO EXPAND THE POPULATION TO CAPTURE ALL AFFECTED BUSES.THE CORRECTIVE ACTION FREIGHTLINER PLANS TO TAKE WILL BE FORWARDED TO ODI WHEN AVAILABLE. ACCORDINGLY, THIS INVESTIGATION IS CLOSED.

ODI WAS CONTACTED BY THE NEW YORK DOT WHO REPORTEDSEVERAL BUSES FAILED BRAKING TESTS WHEN BEING TESTED DURING AN ANNUAL INSPECTION. THE SUBJECT SCHOOL BUSES ARE OPTIONED WITH AN ADJUSTABLE FOOT PEDAL POSITIONING DEVICE THAT ALLOWS THE DRIVER TO RAISE AND LOWER THE BRAKE PEDAL HEIGHT TO SUIT HIS/HER SEATING POSITION.WHEN THE LOWEST PEDAL POSITION IS SELECTED (BY A BUTTON ON THE DASHBOARD), NYDOT REPORTED THAT THE BRAKE PEDAL BOTTOMED OUT ON THE FLOOR, THUS PREVENTING A FULL BRAKE PEDAL APPLICATION.THIS RESULTED IN A REDUCTION OF BRAKE TORQUE AT THE WHEEL ENDS.FREIGHTLINER WILL CONDUCT A SAFETY RECALL TO CORRECT THIS PROBLEM.THE REMEDY CALLS FOR A LONGER PEDAL PUSH ROD BEING INSTALLED IN- PLACE OF THE ORIGINAL PUSH ROD. THEY ALSO INCREASED THE POPULATION TO INCLUDE THE MVP-ER MODEL BUSES.THIS RESOLVES THE ISSUE RAISED BY THIS INVESTIGATION. ACCORDINGLY, THIS INVESTIGATION IS CLOSED.

THIS INVESTIGATION WAS PROMPTED BY COMPLAINTS FROM TWO SEPARATE SCHOOL BUSFLEETS.BOTH FLEETS ALLEGED THAT WHILE MANEUVERING IN A PARKING AREA, THE TIE-ROD TUBE DISCONNECTED FROM ONE OF THE TIE-RODS.DANA, FREIGHTLINER AND THOMAS BUILT BUSES RECENTLY COMPLETED EXTENSIVE TESING AND DETERMINED THAT A CRACK MAY INITIATE ON THE INTERNAL THREAD ROOT OF THE TIE ROD.THIS CONDITION IS DUE TO INADEQUATE DAMPENING IN THE CHASSIS SYSTEM TO ACCOUNT FOR NORMAL BRAKE-INDUCED VIBRATION.THESE CRACKS MAY LEAD TO SEPARATION OF THE TIE ROD FROM THE ASSEMBLY.APPROXIMATELY 5,839 DANA STEER AXLES EQUIPPED WITH A CERTAIN TRW TIE ROD ASSEMBLY UTILIZING A CUT THREAD DESIGN ARE INVOLVED:A.1320 AXLE APPLICATIONS, THOMAS PART NUMBER 61110702 AND 61110705 INSTALLED ON THOMAS BUSES WITH 6" BRAKES AND 30" AIR CHAMBERS;B.1460 AXLE APPLICATIONS, THOMAS BUS PART NUMBER 61110707 AND 61110708 INSTALLED WITH 6" BRAKES AND 30" AIR CHAMBERS. THOMAS BUILT BUS WILL REPLACE THE EXISTING TIE ROD ASSEMBLIES WHICH CONTAIN THE CUT THREAD DESIGN WITH A NEW TIE ROD ASSEMBLY THAT UTILIZES A ROLLED THREAD DESIGN.A ROLLED THREAD PROVIDES LESS STRESS ON THE CRITICAL AREA OF THE TIE ROD. A COPY OF THE DEFECT REPORT IS ATTACHED. THIS ACTION RESOLVES THE ISSUES RAISED BY THIS INVESTIGATION.ACCORDINGLY,THIS INVESTIGATION IS CLOSED.

2001 MVP-ER-140 HS SCHOOL BUS COMPLAINT DUE TO A DEFECT. CONSUMER STATES THAT SCHOOL BUS MODEL LISTED ABOVE CAUGHT FIRE IN THE ENGINE COMPARTMENT. *KB AN ACCIDENT INVESTIGATOR DETERMINED THAT THE FIRE STARTED WHEN PRESSURIZED TRANSMISSION FLUID SPRAYED FROM THE TRANSMISSION THROUGHOUT THE ENGINE COMPARTMENT. THE TRANSMISSION VENT TUBE HAD BEEN CRUSHED BY THE WEIGHT OF THE CROSSOVER EXHAUST PIPE, WHICH WAS NORMALLY POSITIONED TWO INCHES ABOVE THE VENT. OVER TIME, THE BRACKETS THAT HOLD THE CROSSOVER PIPE BECAME LOOSE, ALLOWING THE PIPE TO FALL DOWN AND MAKE CONTACT WITH THE TRANSMISSION VENT. ONCE THE VENT WAS CLOSED, PRESSURE BUILT UP IN THE TRANSMISSION, AND ITS FLUID WAS EXPELLED FROM THE DIPSTICK TUBE. THE INVESTIGATOR'S FINDINGS CONCLUDED THE FIRE WAS THE RESULT OF THE NEGLIGENT DESIGN OF THE CROSSOVER EXHAUST PIPE, SPECIFICALLY THE NUMBER, LOCATION AND OR TYPE OF BRACKETS USED TO HOLD THE PIPE IN PLACE. GIVEN THE RISK PRESENTED BY CLOSURE OF THE TRANSMISSION VENT, IT WAS IMPERATIVE THAT THE PIPE BE INSTALLED SO THAT ITS POSITION RELATIVE TO THE TRANSMISSION VENT WOULD NOT SHIFT OVER TIME. *JB

NHTSA ID

10207155

Incident

May 12, 2005