Reply to Dunegoon - I built my 20" split rims in 1985 to run on a K30 SRW civi truck. Back then, 20" wheels on pick-ups were unheard of. Nowdays, it seems 20" wheels on Caprice pimp-mobiles are commonplace. There may be a source out there making a 20" wheel with the correct bolt pattern, however I have not researched it. I would think the 20" wheels made today would be more for style and decoration, not for strength. And definitely not the split-rim type. My wheel centers are a full 3/8" thick and milled from cold-rolled steel, milled on a Bridgeport milling machine and mig-welded directly to the Firestone split rim exactly in the middle of the rim (no back-spacing). The 11.00/20 NDT is a bias-ply tube-type tire, therefore require tubes and boots. An issue I have had to overcome is the correct balancing of these tires and wheels. Back in 1985 I used standard clamp-on lead wheel weights with OK results, however always had a little shimmy here and there. When I decided to run the wheels on my M1028, I at first purchased a set of HMMWV Balance Masters to run behinind each wheel, however these did not have the capacity to balance the substantial weight of the 11.00/20 NDT tire and wheel. I have since abandoned the Balance Masters and am running 14 ounces of Dyna Beads in each tube with excellent results. The Dyna Beads are perfectly round ceramic beads which, when subjected to centrifical force, move around the inside of the tire or tube and automatically balance the entire wheel assembly. The advantage of this is, if mud or snow gets caked in the wheel, the Dyna Beads automatically compensates for it and re-balances the wheel. My M1028 rides smoother than my wife's Honda.
Reply to Clepto - I don't believe you will be able to get 9.00/20's under a M1009 without major suspension modification. I raised my M1028 5", and still had to cut the fenders and re-position the axles. You should be able to run 9.00/16 with no problem.
