Dunlop makes a 255/85/16 Radial Rover AT, E rated, that is 32. 5 or 32. 6 inches tall and is not that much wider than the stock 235s. My brother had them on his SLT 2500 and loved them. Not sure about the exact dia.
CoastyA8R makes a good point about wide tires. When going to wider tires all little abnormalities are multiplied. If shocks or other components are worn you will feel it now where as before you did not. Air pressures greatly effect ride, the bigger and wider the tire gets. Also, a new tire will ride rougher when new compared to an old worn in set. I air my tires up and down constantly, depending on the load. My trucks are loaded heavy most of the time. This is my eleventh set of BFGs. Ten were truck tires. I have had one flat with them in 24 years. One set on a half ton got 61k miles. Many a time I have sat waiting for others to change out tires in the wilderness loaded with hay, wood or livestock. So until I get burned by BFG that is all I use. The tires listed below are the perfect size for a 2. 5" lifted 1st generation truck. The only problem is that they only make it in a Mud Terrain style. It does wonder on the pavement some, but the performance off road is unbelievable. I can only hope that they will make it in an All Terrain style before these wear out.
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'89, CC, SB, 5sp, 3. 54, 16cm2 housing, maxed fuel, KN, Banks exh w/muffler, Autometer liquid filled gauges, Factory tach option, 100% Dyna-Mat, Horton fan clutch, Firestone air bags, Chrysler V-twin air comp, 2. 5" lift, Rancho Shocks, Alcoa LTS, BFG 255/85/R16 MTs (33. 3")
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