I'm picking up a 64 Fairlane 8 inch rear axle for my project. It has 5 lug axles and I want to convert it to the Mustang 4 lug axles. Do the backing plates and brakes have to be changed over or do the Mustangs have all the same hardware and just different drums?
Ford did make some 8" rears with four lugs for the Mustang II with the V8. Axle bearing sizes are the same, but the brakes aren't; the '64 has 10" brakes, the Mustang II is only 9". I don't know if there is a difference in width, so whether the axles will swap is unknown; good luck finding any these days. You could re-drill the early drums I think but may need custom axles. It will probably be easier to convert the fronts to five lug.
I’m curious why you would want 4-lug axles. Guessing you are trying to match the front bolt pattern on something? Or, maybe just some 4-lug wheels?
Ford used 4 lug on 6 cyl. Falcons in the early 60s, so a full axle swap could be done, providing the measurements are close. As mentioned, they did a V8 strength axle in the mid 70s too. I'd venture that both are going to be a downgrade from current, and also wonder why. You could also have everything drilled and install new lugs, but this seems like wasted effort unless you gotta run some unique wheels or must have a spare that fits all 4 corners. There is a guy who races nostalgia SS who went to great effort to make bolt on caps that look like steel centers for his lightweight aluminum wheels. If you really have to have the 4 lug look, that could be a solution, too. This 4 VS 5 has been hashed out on various OT forums. Many say that the strength difference isn't that great, but parts availability factors in. I won't say it's gotta be 20% stronger, 'cause I'm no engineer.
The early Falcon and Mustang six cylinder cars used a completely different axle assembly with a 7 1/4” (?) integral carriage not related to the later (63& up) 8” in v 8 powered Cars. That’s not the rear you want. I always thought the very early Mavericks had the light duty 7 1/4 integral rear similar to the early Falcon, but I don’t have any concrete evidence of that. Later Pintos had an 8” four lug rear like the Mustang II. Early Mavericks used an 8” with 4 lug axles, and small wheel bearings. Later Mavericks upgraded to the 5 lug pattern, larger axle tube diameter, and bigger bearings, like the Granada, but, I think, slightly narrower.
I have some 5 lug to 4 lug adaptors off a Mustang project if you need them. I think they are about 2 inch thick so could push or wheels out to far.
The early Fairlane was a midsize car, so the diffy wasn't that narrow. I have both the Fairlane and Mustang II complete diffies in my basement but they're a little bit buried, however it looks like the Fairlane is 1 to 2 ins. wider than the MII.
I have done this a lot get one of those plastic wheel pattern disk fit it on the pattern you have and mark the pattern you want mark and grill.
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