THE TIRE, RIM, BRAKE DRUM AND AXLE SHAFT SEPARATED FROM THE AXLE HOUSING. THE ASSEMBLY WEDGED UNDER VEHICLE. WHEN IT POPPED OUT, IT FLEW UP AND LANDED DIRECTLY IN FRONT OF ANOTHER VEHICLE. WHEN THE ASSEMBLY SEPARATED, APPARENTLY THE OTHER (REMAINING) DRIVE WHEEL BECAME DISCONNECTED FROM THE ENGINE; OUR EXHAUST BRAKE COULD NOT SLOW US DOWN. ADDITIONALLY, THE BRAKES WERE SPONGY, AND APPARENTLY NOT WORKING. WE SLID TO A STOP ON WHAT REMAINED OF THE AXLE HOUSING. WHEN WE EXITED THE VEHICLE, THERE WAS A FLAME SHOOTING FROM THE END OF THE AXLE HOUSING, WHERE THE AXLE SHAFT WOULD NORMALLY BE. THIS FLAME WAS APPROX. 1.5-2 FEET FROM THE FUEL FILLER TUBE. IMMEDIATELY PRIOR TO THE ACCIDENT, THERE WAS A VERY LOUD SCREETCH SOUND. WITHIN A MINUTE, THE WHEEL ASSEMBLY CAME APART. AFTER REPAIRS WERE MADE, THE SAME AXLE PROBLEMS REAPPEARED.