Rear end lengths

[NewtoBBodies72]

I am looking to purchase an 8 3/4 rear end for my 72 Satellite. Currently saddled with the 8 1/4. Where can I find the factory specs on lengths for this year? I understand that there are several different lengths for B Bodies depending on the year.
I have looked at a few online and at swap meets but have not been sure enough regarding the length in order to purchase.
Also, if anyone can give me specifically where to measure length...outside drum to outside drum or inside axle shaft to inside axle shaft. Any help is greatly appreciated.

 

[davek]

what did the 83/4 come from ,did you look on http://www.mymopar.com/index.php?pid=31

 

[Extremespeed]

I am looking to purchase an 8 3/4 rear end for my 72 Satellite. Currently saddled with the 8 1/4. Where can I find the factory specs on lengths for this year? I understand that there are several different lengths for B Bodies depending on the year.
I have looked at a few online and at swap meets but have not been sure enough regarding the length in order to purchase.
Also, if anyone can give me specifically where to measure length...outside drum to outside drum or inside axle shaft to inside axle shaft. Any help is greatly appreciated.

Try this link it should tell you everything you need to know. https://www.bigblockmopar.nl/tech/mopar-rearaxle-dimensions/

 

[Cranky]

And once you know what size you need and find something at a swap meet that might be a quarter inch difference, don't worry about it because they're not always exactly by the book.....

 

[Big Bad Dad]

Aren't the spring perches spaced and angled differently on the 71 up B bodies from the earlier years?

 

[PurpleBeeper]

Aren't the spring perches spaced and angled differently on the 71 up B bodies from the earlier years?

The perches are farther apart, but I always "thought" the angles were the same...but I don't know for sure.

 

[Dipstick]

Here's pinion angle info from Doc Diff:

A-body perch (level): pinion 5 degrees up
B-body perch (level): pinion 4 degrees up
C-body perch (level): pinion 3 degrees up
E-body perch (level): pinion 6 degrees up
FL perch (level): pinion 3 degrees up

 

[Crackedback]

That chart on the mymopar site needs to be burned. It's got so much incorrect info on it. Been around for years and screwed up MANY people.

 

[YY1]

Sticky in the axle section right here on this site.

71-74 B body 8 3/4 is kinda hard to find.

E body is real close, a lot easier to find a cheaper when you do.

 

[rrTor-Red]

This too

 

[Crackedback]

This too

View attachment 715025

That is the garbage POS chart... ugh...

 

[Dipstick]

This too

View attachment 715025

That one needs to be deleted from the WWW.

 

[rrTor-Red]

That is the garbage POS chart... ugh...

K. Does someone have correct measurements? I'm looking at a rear end from a 71-72 Charger for my '71 RR (8 3/4). I want to make sure

 

[YY1]

https://www.forbbodiesonly.com/moparforum/threads/8-3-4-axle-chart-the-good-one-sticky-please.60032/

 

[rrTor-Red]

THANKS YY!!

 

[JoePole]

Not sure what you vehicle needs are but 8.25 with sure grip is good for 400 HP. A one legged 8.25 driven hard (burnouts,etc) may not survive a high HP application. Cheaper to keep her.
One option is to find a an 9.25 rear out of a 75 and up B body. They are hard to find but will bolt right in. Another way to go is to find a newer 9.25 with disc brakes (Ram, etc). You will need to shorten and get new axles but the swap is relatively cheap.
9.25 axles are very strong and a lot cheaper than 8.75.

 

[NewtoBBodies72]

Thanks for all the info. I think I will be more confident when looking.

 

[YY1]

Also keep in mind that 73 and newer will be a ISO-comp spring mount ad will need to be addressed if going on a 72 shock plate.

An 8 1/4 sure grip unit is not terribly expensive, but there's a fair amount of specialized labor and tools required to install it.