THIS AMBULANCE WAS INVOLVED IN A MODERATE FRONT END COLLISION. IT APPEARS AS IF THE OUTER WHEEL BEARING RETAINER NUT FAILED CAUSING THE NUT AND OUTER BEARING TO BE EJECTED FROM THE HUB. THIS APPARENTLY OCCURED ON IMPACT. THE AMBULANCE WAS TRANSPORTING A PATIENT AT THE TIME TRAVELING AT REASONABLE SPEED. ANOTHER MOTORIST ENTERED THE PATH OF TRAVEL OF THE AMBULANCE. TFC OFFICER(I) SOME BACKGROUND IN THE AUTOMOTIVE REPAIR AREA AND FEEL THAT THE SPINDLE NUT SHOULD NOT HAVE CAME OFF. I COULD NOT FIND IT SO I DON'T KNOW IF IT BROKE. CASE #01007413