Engineering Analysis · FRONT TIRE FAILURES · Opened 2005-07-14 · Closed 2006-08-30
Investigation
Action number
EA05011
Type
Engineering Analysis
Open date
2005-07-14
Close date
2006-08-30
Manufacturer
COUNTRY COACH INC
Affected makes
COUNTRY COACH
Affected components
TIRES
Affected model years
1995, 1996, 1997, 1998, 1999, 2000
Affected (make, year) variants
11
Summary
ON JUNE 30, 2006, COUNTRY COACH FILED DEFECT REPORT 06V-262 STATING THAT THE TOYO 275/70R22.5M102Z TIRES ARE DEFECTIVE AND COULD FAIL UNEXPECTEDLY CAUSING A LOSS OF VEHICLE CONTROL.ODI'S INVESTIGATION FOUND THAT FRONT TIRE FAILURES HAVE BEEN CAUSED BY COUNTRY COACH'S SELECTION OF TIRES THAT PROVIDED MARGINAL LOAD CARRYING CAPACITY FOR THEIR INTENDED APPLICATION.OWNERS WERE FREQUENTLY UNABLE TO COMPLY WITH COUNTRY COACH'S CAMPAIGN REQUIREMENTS BECAUSE THESE REQUIREMENTS WERE INEFFECTIVELY COMMUNCIATED AND BECAUSE SPECIFIED TIRE INFLATION PRESSURES WERE DIFFICULT FOR OWNERS TO ACHIEVE AND MAINTAIN. ODI ALSO FOUND THAT THE RUBBER PROPERTIES OF THE TOYO 275/70R22.5 M102Z DEGRADE WITH TIME. THE DEGRADATION IN RUBBER PROPERTIES DOES NOT PROVIDE ANY OBVIOUS INDICATIONS TO THE VEHICLE OWNER AND THE TIRES BECOME MORE SUSCEPTIBLE TO FAILURE OVER TIME WHEN SUBJECTED TO THEVEHICLE OPERATING CONDITIONS DESCRIBED ABOVE.