A winch or someone with a winch in the group.
Tow points on all vehicles front and back.
A good spotter also goes a long way on a lot of these runs.
My YJ has a 3.5" lift with 33s and I haven't ran into too many issues. Again, a spotter will go a long way. Also, good judgment is something that will help out in the Alaskan wilderness. We spent about 18 hours on the Eska run because we decided to press on when the weather turned on us. We had 5 rig, four of which had winches, and it still kicked our asses. Had we turned back when the ominously dark clouds moved in, we would've been just fine. I'll find some pictures of that day and post em.
[SIZE="3"][B]Check the air tires, thats where the power is generated.[/B][/SIZE]