Thats funny. I get to driving and it needs gas and I put it in. Then I drive it til it needs it again. The speedo is off with the 35's so I am not sure what I'm getting, Running 31's your going faster, speedo is slower. So you are actually going further than odometer is saying, so you can only use it as a guide.

89 SWB, V-6 5SPD, OME Shocks, 16.5X37's, 2"BL, SR axle, Gen2 brakes, Lincoln w/Superwinch