Hey guys, my truck is reg cab short box stepside and i am looking for a way to transfer some weight onto the back wheels for this upcoming winter. That and i just want to level out my truck. Ive been told that the kit with just the two shackles changes the angle of the driveshaft, therefore causing the U-joints to wear out faster. Ive seen a kit that comes with 4 shackles and it relocates front and rear mounts for the rear leaf springs, therefore keeping the driveshaft in line. Can someone give me some advice on which kit to go with? Is this likely to void my factory warranty? I appreciate any input on the subject. Thanks