I just got a nice clean 97 OBS
. 7.3, auto, 4X4
4:10 gearing. I will be doing the 6637 air filter setup and 3" dp
with 4" back and maybe a TS 6 pos chip. What kind of mileage gains should I see? Thinking of doing 1 or 2 stack setup also??? I am in the middle of putting new ball joints and front axle joints at the moment then tires. I would like to go a bit taller but skinnier than 285/75/16's and was leaning twords a set of 255/85/16's. I work in a shop and can order just about any tire I need at cost. What would be the tallest I can put on this truck? It is the F250 HD if that makes any diff in front end springs.