Genopsyde

iTrader: (2)

Yesterday evening, I came across a complete Ford 9" out of a 79 pickup for $100. It is NOT bolt in ready for my f-body, so I will be doing the modifications myself, which is the way I prefer anyway. I was just curious if there were any members here that have done this already and could offer any tips, advice, pointers, etc...

I haven't checked any casting numbers yet. I will do so and post them tomorrow or later in the week. Thanks in advance.


Edit: Found some good info here: https://www.thirdgen.org/forums/tran...-end-hard.html

AlkyIROC

Sell it and buy a direct bolt in diff. By the time you're done modifying the wide truck diff to fit under your car, it will probably cost you more than ordering the direct bolt in diff. Measure axle flange to axle flange on both the third gen diff and the truck 9" to see how much different the width is. Not all 9" diffs are the same.

If you have enough fabrication skills, anything is possible. How much is your time worth? How good/safe are your skills? Generally if you're asking on how to swap a diff not designed for a third gen, you shouldn't be doing it.

Chances are it's a C7AWE center section. That's the most common late model center. The pinion support is weak. I've seen 11 second vehicles spit a pinion out the side of the diff when the support breaks. I pushed one into the 9's before finding the housing cracked. I replaced the case with another used one before it failed to get me to the end of the season then bought a new aluminum case.

If it's 28 spline axles, throw away the carrier (posi) and buy one for 31 splines. If it is a 31 spline carrier, you can start using it and upgrade to a better posi in the future. You're going to need to upgrade to aftermarket axles anyway to get them to work with GM bolt pattern rims. What about the brakes?