Ok here my deal I have an 87 f350 4x4 with a 4 speed manual trans. Dana 60 in the front and Dana 80 in the rear with 4.56....I'm looking for 3.55 to get the r.p.s down. I'm running 2700rpm at 55. so any ideas where I can find what I'm looking for...can be new or used. I looked on rockauto.com but they don't have any thing for Dana 80 well I could find any thing on there lol

Thanks guys

 

Zumbrota Bearing & Gear in Zumbrota, MN. These guys do great work. Not sure what it would run you but I'm pretty sure they can find what you are looking for.

 

Might be cheaper swapping in a 5 speed, I am sure you will spend $400-500 to swap gears.

 

Try Googling Dana 80 gears, this might get expensive in a hurry, you ll need carriers too . Dodge used these axles too, here's a little bit from a diesel forum,
http://www.cumminsforum.com/forum/ge...gear-swap.html