My '12 F150 with 3.7 V-6 and 6 spd trans & 12k miles, feels like something is lose when I'm coming to a complete stop. Just as truck stops moving, it feels like the front u-joint is lose and there's also a small but noticible bump when you start off again from a stopped position, like from a traffic light. This is my first expereince with a Ford truck in a long time, so is this characteristic of this drivetrain or should I be heading for the service dept.? It just doesn't feel right to me and as time goes on, I would think it will only get worse. Any thoughts?