i am having same issue, i have sway away coils with some preload and 275/70/18 tires and recently noticed squeeking only when i turn the steering wheel at low speed or sitting still, got my steering rack checked its fine, replaced sway bar bushings and got some prg sb endlinks and its still there, annoying, but i do believe it is the sb bushings because of poor design when you tighten them they pull apart at the split and dont "seal" around sway bar so i figure thats the problem-i just ordered some from infinity for qx56 that are designed different and look like they fit way better.