WHILE DRIVING ON TURNPIKE, A PASSERBY SIGNALED CONSUMER TO PULL OVER, ONCE HE PULLED OVER AND GOT OUT OF TRUCK, HE NOTICED SMOKE COMING FROM THE TRAILERS FIFTH WHEEL AXLE AROUND THE LEFT INSIDE TIRE, CONSUMER WENT BACK TO THE TRAILER AND SAW FLAMES, CONSUMER TRIED TO EXTINGUISH FIRE BUT WAS UNSUCCESSFUL, THERE WAS NO DAMAGE TO THE TRUCK ONLY THE TRAILER, THE FIRE DEPARTMENT WAS UNABLE TO DETERMINE AN IGNITION SOURCE FOR THE FIRE.(OHIO TRAFFIC CRASH REPORT # 10-92-339)*JB