Axle housing flange?

[cazsper]

I'm looking at a set of brakes for the rear of a '73 Mach-1. When it comes to the axle flange of the 9 inch, what axle flange is it? There's a Big Ford, Big Ford (new style), and a Small Ford.

 

[oh dam]

Honestly i wondered the same exact thing, so one day i had the car jacked up and looked back there it looked like either the 8.8 ford or big ford new style. Keep in mind i have an 8 in. So moral of the story. look in the back of the drum you dont have to take off anything just peak your head back there and look at the flange and much it up

 

[Don C]

8 inch and small 9 inch have the same flange, with bolt spacing of 2"x3-3/8". Big 9 inch are 2-3/8"x3.5", New 9 inch are 2"x3-9/16".

 

[mdan575]

I was looking at the kit below for an easy upgrade for my 71 with a 9". Simple bolt on is nice sometimes instead of hunting down all the conversion parts from another ford car.

http://www.ebay.com/itm/261373816640?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

 

[cazsper]

I wasn't looking for a bunch of parts, I was looking at a kit from Bear or Wilwood. It's just tjat they asked about the axle flange.

 

[Don C]

Before ordering I would measure, just to make sure. You're going to need to put it on jack stands and pull the axles, anyway, to take the backing plates off. Another indication of flange size, 28 spline axles just come on small flange rear ends.

 

[Jeff73Mach1]

If the rearend in your car is original to a 1971-1973 Mustang and is a 28 spline unit , then it is a small ford-whether it is an 8" or 9"

I believe this to also be true for 71-73 Mustangs with the 31 spline axles-but cannot say so to the same degree of certainty.

28 spline axles will have a squared off oval cut in the center while 31 spline units will have two round holes in the center