I just purchased a 2007 Sahara with a 4" lift 37" tires.. The lift is all well and good. The engine seems in great condition 85k. However there is a slight rattle noise in the front end seemingly below the drivers feet when starting off from a stop (not every time). I'm new to the Jeep world. The lift was done with "procomp" and "fox" however it doesn't look like anything was done to the axles. What issues could this be having?