new to the site, might add I love my 2006 F150 FX4 5.4. I recently chansed plugs, wasn't that bad after I bought the lisle tool, had to replace struts, then had the upper and lower ball joints replaced. I did the struts myself, but I think I did something wrong. getting a knocking noise on bumps. looks like the nnut on top of strut is moving up and down, but I can't it any tighter, any suggestions.