Just got a 8.75 but what's it out of?

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mellow_utah

mellow_utah

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Hi all, I just did a 360 swap in my scamp and still have the 7.25 sure grip. Found a 8.75 yesterday that was the correct width so I bought it and I'm wondering what's it out of. So far I've figured out its the 1964-72 small stem(741) diff, with open 391 gears. What's throwing me off is it has reverse lugs so it must be early but the spring perches are on top of the axle tubes instead of the bottom. I'll have to swap them for my application. Did the trucks or the a100s come with the perches on the top? There are some painted numbers on the drivers side axle tube that are 976 and what looks like (A 10 P). Anybody have any idea what it came out of?
 
Here is a good source of 8 3/4" info. Unfortunately, I didn't see anything close to the numbers you posted. I guess there isn't another casting number along that thick "rib" at the very bottom of the casting where most other 8 3/4's have their #'s?

If the perches are on top, I would think it came out of a truck.

I'm starting to think I posted this in the wrong 8 3/4" thread, but I hope it helps anyway.

[ame]http://bionicdodge.com/Download/Mopar_8_3_4_Rear_End_Guide.PDF[/ame]
 
It measures out to be for an a body, 57 1/8" drum to drum and 43" center to center on the spring perches which is correct. According to the link, it's a couple inches narrower than other axles. I don't get the fact that the perches are on the top though
 
Perches on top is a truck or van thing. L/H studs where used on the L/H side until, I believe, 1972 (This may be wrong, certainly as late as 69 used them). Many trucks and vans also used 3.55's and 3.91's.

Here is some more good reading on the 8 3/4 if you have not already seen it.

http://www.bigblockdart.com/techpages/875axle.shtml

If it is the right width for your car just weld on another set of perches below, make sure that you have the pinion angle right!
 
If you're going to weld in another set of purchases, you might as well get an offset shackle kit.
 
You have a pickup 8.75" rearend. It is much wider than 57", however.

"Drum to drum" is measured between the wheel mounting surfaces, not between the inside of the drums.
 
Crap, youre right, so does anybody know of a place that sells the flanges (to bolt the drum on) and spring perches so that I can get it narrowed? Is there welding required on the spring relocation? I dont have a welder so it would be a bit of a pain to do that if it requires it?
 
Narrowing, Spring Relocation, etc all require welding.

New Housing Ends can be bought from multiple places (Strange, Moser, etc), same goes for new Spring Perches (I usually reuse my old perches). You'd also need new Axleshafts to match the new/narrowed width of the rear (or if you have suitable axleshafts, shortened and resplined)

It's not a project for the faint of heart, best left to a shop that has done that sort of work before, or to a company like Strange, Moser, etc.
 
I also dont think it will work with my rear swaybar. I would imagine if I had a shop do the perches, shortening to a factory speck I could order new axles easily enough for a stock a-body housing from somebody like mosier.
 
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