That is a big jump. What engine and gearing were you running and why did you only run the 31s for such a short period? With the 29s and 3.73s it will bark the tires and pull hard uphill. No rocket for sure but it goes plenty fast. OD/fifth gear is useless until the speedo hits 70 (roughly 78 mph).

I like the look and performance of the 235/75s but some bfg at 31s look tasty.

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1996 Splash SupreCab, 3.oL, 5 speed, 3.73, Rough Country 1.5" levelers, 31x10.5 Nexen Rodians