NICE! 4" lift over 35s? Got mine back on the road after 18 months thanks to divorce and medical issues with parents. Had to de-varnish the injection pump, install Air Lift on the rear and new 33s all around.
Why Air Lift? Tools. Lots of tools. Miller Dynasty 200 DX with full kit of welding tools like 12" and 8" C-clamps, a set of 25 foot tow chains in 3/8 and 5/8" sizes. Air impact tools, full 1/4, 3/8 and 1/2 sockets, argon, oxygen and acetylene plus Victor 100 gas setup. It was sagging bad, probably from towing a tandem for a combined weight of 16,800 pounds without use of a weight distributing hitch.
So I also put a Class V hitch on it which can take a WD hitch too. Its looking good.