First off im installing a 94 12 valve in my f-350 it has a zf5 trans has 4.10 gears as of right now. What gear ratio works best with 315/75r16 tires? ( Pretty much 35 inch tires )Truck will see daily driving and the occasional heavy trailer.

 

them 4.10s should do pretty good!

 

I think the 4.10's will do just fine. With a 0.76 O/D ratio, RPM's should be decent on the hiway, but you'll still have good grunt to get the load moving.

 

Thanks guys

 

I like 3.73 but 4.10 will be fine