The only bolt-in 8.5 axle housings for a G-body were the ones used on the 1984 Hurst/Olds, the 1985-87 442, and the 1984-87 Buick GN. Every other G-body got the 7.5. Nothing else is a direct bolt-in, so these axles sell for stupid money when you do find one. The Olds axles were all 3.73, the Buicks were all 3.42. No, posi was not stadard, it was optional.

Yes, people have used the A-body axles under the G-body. The mounting ears are in the wrong place, so unless you use the special control arms with metal ball joints, the suspension binds up. These are not inexpensive. The A-body axle is also 4"-6" wider than the G-body, depending on year.

 

What would you recommend as far as a good and easy to find rear end. Because I’m pretty new to the rear end game and I’m trying to convert to a two wheelie lol

 

If your real question is "affordable" axle, you are out of luck. As I said, the G-body community has run the price of the bolt-in 8.5 out of site. Unless you want to pay dearly for a brand new axle like Moser or Currie, there are no other "bolt in" solutions. Others have adapted the Ford 8.8. That still requires custom control arms, redrilled axle flanges, and a custom driveshaft.

 

One more question, Couldn’t I just upgrade my axles on my 7.5” and get a good posi unit?

 

Yes, that is an option. Of course it won't be as strong as an 8.5. Depends on how much torque and how much traction you have.

 

Find a good used gear set out of 3.42 or 3.73 gears out of the 4 gen Camaro, they are 7.625" whch will fit, with the Torsen worm gear posi, just the gears an carrier. Or a new quality gear set with the Detroit Trutrac, basically the same posi. Also get a girdle cover and 28 spline Moser axles.

 

'94 and up Mustang 8.8.
BUY: Adjustable upper control arms, spherical bearings for upper housing bushings, 1310-3R-Gr u-joint, Ford driveshaft flange, drill guide for bolt pattern ( http://www.rottenleonard.com/Menu.html )


Cut off old spring perches
Weld on spring perches
Drill the axles


Even the center brake line threads into the factory G Body one.


https://gbodyforum.com/threads/8-8-i...p-enjoy.17317/

 

Well I would say a MUSTANG rear is not an easy bolt in direct option for this guy NEW TO DIFFERENTIALS...lol
You 7.5 will survive quite well
We have done plenty of 28 spline axle upgrades and a good aftermarket Eaton or Auburn limited slip posi and aftermarket ring and pinion with great success.
The motor and combo you have on the street will be absolutely fine with the stock rear upgraded.
If you PM I think we have a set of 28 spline axles NO BOX deal and limited slip and gear no box deals we get all the time from buying out tranny shops that do not want to do rear ends anymore. Performance show table display stuff etc.
We usually just put it up on eBay to unload.
Give a PM will help you out.

Jim
J D