I have been running Cooper radial truck tires, LT215/85R16 (5.5" recommended rim width) on my original 1954 4.5" rims. When installed, the tires have a high profile (looking a lot like original bias-ply truck tires) and have a wider installed/loaded diameter (about 31.5") than when installed on a 5.5" or wider rim (about 3.26"). These tires have worked fine for six years, but I travel less than 2,000 per year (and never at speeds above 65-70mph and at loads of 200-1,000 lbs).
