12 bolt rear

[88ss408]

hey does anybody know the diffrence in width of a g-body rear to a A-body rear ?

 

[husky100]

A body rear is wider by I think 3" maybe 4". A body rears will work but with some modification.

 

[pontiacgp]

it's only an inch wider, 1/2 inch on each side...get the driveshaft with the rear if you can cause you'll need a driveshaft 1/2 inch shorter

 

[85 Cutlass Brougham]

I think it is more an issue of the mounting points for various suspension pieces that keeps it from being a simple bolt in.

 

[husky100]

Thats correct!! Backing plate to backing plate on a G body 7.5 is either 52 or 54 I keep forgetting but the A body 8.5 is 55.5 or 57 again I cant remember but I will go measure if you really need the measurements as I have several of both. What creates the problem is the upper and lower control arms as the angle is different. They do make upper and lower conversion bars but again for me it was not worth the hassle. Also the shocks may also be a little different as well in regaurds to the mounting location. I would do some further research before making my decision.

 

[81malibag]

A 10 or 12 bolt rear will bolt in a G-Body car. You have to re-drill the upper control arm bolt hole on control arm (near crossmember) 3/4" on center inwards toward rearend. This will give you proper yoke angle. Your stock driveshaft will work & Napa auto parts sells the cross referenced U Joint for around $11 bucks & with a lifetime warranty. Good luck.