My body guy at the shop the Charger's at would let me have this old 12 bolt housing and stuff he's got laying around for free but right now I don't have a clue where to start to make it fit the Chicken...

What I know... old 12 bolt out of a ???? Has the fittings on the housing to bolt up to an old 4 link full frame car (Chevelle maybe?). 55.5 inches from end of axle tube to other end. No axles, no gears.
Also has an unknown clutch type posi unit sitting with it (has 6 7 2 stamped into it) that will take 31 spline axles and a couple of brake drums.

Anybody ever try to make something like this fit??? Where would you come up with a torque arm mount for this kinda thing?

I got a '90 10 bolt sitting in the garage that I guess I could cut the spring perches and stuff off to weld onto this thing but other than that I'm not even sure at this time if the width is correct.

 

Hit search... answer my own question... I guess it can't be done...
oh well... it was worth a shot.

 

its possible, but i belive you need to narrow the axle tubes, weld in all new spring and shock mounts and the torque arm, agian it can be done, but a major pain in the ***, only thing you can do is try to build up the 7.5 or get a moser 12 bolt and be done with it

 

It was just a thought at trying to solution my worn out posi in the GTA and possibly upgrade the Chicken at the same time. Ordered a new 9 bolt carrier from Miles. I'll worry about 12 bolt if I blow up the Chicken's rear again this year.

 

is the cover of that 12 bolt pretty much round or is is pretyt irregular shaped ? i wanna know if its a truck or car 12 bolt, that date code of G72 makes it a June 7th 1962 or 1972, and im pretty sure was no car 12 bolt in 62, so must be a 72, but thats the last year of the car 12 bolt..

 

I'll have to go back and look again. I'm not a 12 bolt guru... that's why I was asking. He didn't even know where it came from.

 

i know hehe, i was just posting most obvious difference between the two, but im curious myself too, so lol


good luck@

 

Unless you plan on doing a lot of rear suspension fabrications it's not worth the money to try and adapt an old 12 bolt. There's no way to attach the torque arm onto the diff. A ford 9" housing is steel and mounts can be easily welded onto the housing. The center of the 12 bolt housing is cast iron making it very difficult to attach a torque arm mount.

You could install it but change the rear suspension to ladder bars or a 4-link but by the time you're done it would be cheaper to buy an aftermarket 12 bolt.

 

If you can get it for free, get it. The center section and backing plates will fit the after market 12 bolts, if it's in fact a car 12 bolt. Getting the axles resplined will also be cheaper than buying new ones. Then if you find out for sure what kind of car it came from there's good old ebay. There are plenty of guys out there looking for 12 bolt housings for Chevells & GTOs.

 

You can fit a 12 bolt in a thirdgen. Heres a tech article that might help.
http://www.y-t-g.com/12bolt.html