With the amount of power those engines put out, I wouldn't put another axle behind it. Just gimme a good Ole Jeep 4x4 with the 4.0 or a 4bt and call it good enough.
Bazinga. I couldn't agree more that if this were going to be a serious off roader something more stout is needed under the hood to drive all 6 wheels. The Hemi V8 in the bigger Jeeps comes to mind.