Tie rods are all tight. Only rumbling and vibration I get is after starting the truck up and pulling out of a parking spot. Only feel it in pedal and steering columnAlso, if the tie rod ball joint is bad or going bad normally you would feel vibration through the steering wheel at normal highway speed. Grab the tie rods and if they are not tight then I would replace them. Tie rod separation at speed would not be a pleasant thing to have happen. Please let us know on the outcome.......