[THEFERMANATOR]

4 doors have a different front end set-up which is why they sit lower. If you measure em out, you'll find that the front torsion bars are about 1/2 the diameter and roughly 3 inches shorter than the others that GM used for full size trucks. This is why the 4 door TAHOE never received the 6.5L diesel as they just couldn't fit in with the relocated front torsion bar crossmemeber and didn't want to make new torsion bars to handle the extra weight. All of this was done because GM wanted to put the fuel tank in front of the rear axle on the 4 doors so the spare tire could go underneath to give more interior room.