i have a 77 f250 4x4. i thought i had a dana 40 but reading some of the post here im beginning to wonder if i have a dana 44 hd. new to this stuff so im not even sure if there the same thing. i have a 4.5" hub. its also a highboy. are there any charactistics that difine the 2 that i can look for. id like to know since i have to get some front gears for it. also i was thinking of just replacing it with a dana 60, but not sure one what a good used one will cost or if its worth the hassel to go through it. how much stronger are they and what could i be looking at at getting one and trouble of replacing it.

 

This site has a good guide for IDing axles. Scroll down the L side bar to "Diff & rear axle components", then scroll down the main window to the Dana section. This page is also on that site, but I don't know how to find it there.