Hey guys, I have a '56 f-100 with a 302 and a C-4. Has the original Dana 44 3.78 gear. It needs a taller gear in the rear or something more expensive like a AOD. If I go the new ring & pinion, what would be a good all around gear? Like maybe a 3.55? Any thoughts on the AOD swap? What are the major mods required for an AOD?
Thanks for any suggestions and help,
Jay

 

Welcome to FTE we Love pictures and would like to see your truck.

Your rear gears really depend on what you're going to do with your truck. If your going to race it then keep the high ratio gears and add a AOD or manual OD tranny. If you mainly cruise then probably your best bet is deep six the Danna for a 57-72 F-100 9" rearend.
Here's a calculator to help you find the right gear ratio vs RPM. Differential Gear Ratio Calculator

 

Welcome to the forum!

What diameter tires are you running?

I would think something more like 3.25 if you keep the C-4 and have short tires (modern low profile).