PE 00 020/TIRE TREAD SEPARATION: WHILE PULLING A TRAILER, WITH A 1989, FORD, F250: ORIGINAL EQUIPMENT, LT237/85R16 AND DOT# UNAVAILABLE. AT 60 MPH LEFT REAR TIRE EXPERIENCED A BLOWOUT/TREAD SEPARATION, CAUSING LOSS OF CONTROL. VEHICLE/TRAILER WERE FORCED INTO A DITCH. FIRESTONE NOTIFIED. PLEASE FEEL FREE TO PROVIDE ANY FURTHER DETAILS. *AK