Two days ago I got in my truck and backed out the driveway. Soon as I turned the steering wheel to the left I got this knocking sound coming from the drivers side front, felt it in my feet. Ever since then I get that knocking(just one, sounds more like a thump) every time I turn to the left. Had the truck up on jacks rotating the tires Sat and wiggled, pulled and gave everything a shake---nothing moved and everything looked(??????) fine. The only thing I found out of the ordinary was the front shock seemed to move easily.Anybody got any ideas?