The motor running boards, the aluminum piece that suppose to hold the running boards to the vehicle, broke off without any warning. how does this happen? i am driving, stop at the light and make a left turn, and all of a sudden i hear these sound like my running board are sliding out. i pull over and the entire running board is hanging out completely away for the vehicle. luckily there was no other cars beside me. i had to push it back in and drove very slowly so it would not fall back out and hit another car. this is dangerous and could have cause a serious car accident. the running board needs to be checked on all 2006 lincoln navigators as soon as possible.