I've got an 01 F150 supercrew and am getting some wobble in the steering wheel sometimes (turning back and forth maybe an inch or so). Seems to happen mostly around 40MPH and up, but it isn't always consistent. I don't have any lift kits installed and have standard tires on it. I did replace the shocks (Monroe SensaTrac in the front, and Monroe LoadLevelers in the back) on it like 6000 miles ago, but didn't notice any correlation between the two. Any ideas what might be causing this? Maybe some parts in the front suspension need replacing?