Strange find with the rear drums.

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Williamsburg Virginia area
My Car
1972 H code convert., 351C 2V, FMX, 9in., Ram air, Pwr Steering, Pwr Disc brakes, air-conditioning, 15" sport wheels, Ivy Glo w/white deluxe interior.
Today was also a day I started to dismantle the rear brakes. After looking at posts, additional info on other sites and actually measuring the width, I determined the rear drums were the 1-3/4" variety so, I ordered the corresponding shoes. Held off on the drums until I could remove one and determine if they can be cut and they can. Really good shape too so I could almost get away with new shoes alone.

Now for the surprise; they're 2". Everything pointed to the middles size unless I totally mis-read something somewhere, but I thought the 2" drums were on the large bearing 9" in the Mach 1 and Boss?
 
I have a 302 with stock 8 inch rear and 2" rear drums.
Well, that blows that thought out of the bleach box. I don't know where I read it or saw it but I swear it was. Anyhow, off to find 2" shoes. Really wanted to upgrade to disc's but that's more a vanity thing than need and the cost sealed the deal. I really like how the disc's on all four corners looks but then again, have the Magnum 500's so more difficult to see.
 
Today was also a day I started to dismantle the rear brakes. After looking at posts, additional info on other sites and actually measuring the width, I determined the rear drums were the 1-3/4" variety so, I ordered the corresponding shoes. Held off on the drums until I could remove one and determine if they can be cut and they can. Really good shape too so I could almost get away with new shoes alone.

Now for the surprise; they're 2". Everything pointed to the middles size unless I totally mis-read something somewhere, but I thought the 2" drums were on the large bearing 9" in the Mach 1 and Boss?
All models got the same brakes. If you opted for front disc or power ,those were your only two options. Makes no since,but standardized
 
Now for the surprise; they're 2". Everything pointed to the middles size unless I totally mis-read something somewhere, but I thought the 2" drums were on the large bearing 9" in the Mach 1 and Boss?

There are two width rear shoes used on the 71-73s. 1 3/4" on the 71-72 8" equipped cars ( 250-6, 302-2V) and 2" on the 351 and 429 cars with the 9", and all 73s. There's no "large bearing" 9" rear axle used in the 71-73s, they all use the same housing and the same axle bearing.
 
Well, that blows that thought out of the bleach box. I don't know where I read it or saw it but I swear it was. Anyhow, off to find 2" shoes. Really wanted to upgrade to disc's but that's more a vanity thing than need and the cost sealed the deal. I really like how the disc's on all four corners looks but then again, have the Magnum 500's so more difficult to see.
Or....the Aerostar 10" x 2 1/2" drums and shoes bolt on conversion. Looks stock, but an extra 25% friction area compared to the 2".

Other options:

https://mustangsandmore.com/ubb/RearBrakesbySamGriffith.html
 
Or....the Aerostar 10" x 2 1/2" drums and shoes bolt on conversion. Looks stock, but an extra 25% friction area compared to the 2".

Other options:

https://mustangsandmore.com/ubb/RearBrakesbySamGriffith.html
While the idea of that sounds appealing, if I'm going to swap the system for anything, it's gonna be discs. That may end up happening anyhow given the situation discovered when I pulled the drums. The amount of oil buildup can be any one or a combination of both the brake cylinders and seals. I have the tools to do a rebuild of the cylinders but the seals will lead to more than just replacing those, there's something I agreed that happens, in another thread, it's the "while I'm there" conundrum.

While I'm there, might as well do the bearings. That'll lead to pulling the "pig" (third member) and that's something that will cause an issue with the DW. The smell is bad, really, really bad, especially when the garage is attached and the house is buttoned up tight since it's winter, even here in coastal Virginia.
 
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