I own a 2003 2500HD,2wd, Dmax/ally, GMC Sierra, crew cab, short bed. I lowered the truck with a McGaughys spindles, rear spring frame mounts and rear shackles. I also installed a set of Energy Suspension polyurethane bushings in the front suspension. Here is my problem. I have been hearing a cracking or clatter in the right front when I turn into a filling station drive causing the front to be in an off camber situation. I knew the sound was in the suspension but couldn't find it until today. It is not the sway bar links. While replacing the bump stops which have gone bad I found the holes in the frame mounts thru which the lower control arm bolts pass are ovaled out. I guess the bolts have worked loose or I did not tighten them properly. Either way does anyone have an idea about how to repair the holes in the frame mounts? ? I have an idea but it will be tedious. Maybe someone will have an easier fix.

I have used these in a few situations like yours http://kartek.com/Product/Fabrication/Washers.html
get the 5/8 ones and drill them to 11/16 or 18mm prefered that is the bolt size. just use a uni bit to elarge the original hole to 1" for the shoulder to fit in. no welding needed.
Or use some 3/16 plate or strap and drill the 18mm hole in it and trim to fit the crossmember and weld in place.