what are the casting numbers for a 71-72 8.5 ring gear housing?

 

What do you mean by ring gear housing? Are you referring to the rear axle assembly or the carrier that the ring gear bolts to?

 

the axle housing

 

looking to ID a 71-72 versus a 73 up

 

Here's a pic of my 1971 8.5" 10 bolt:

 

a friend has a barn with a bunch of olds stuff, he says he has a couple that he thinks are 71-72 8.5, wants $100.00 each. I mussed out on 2 Chevelle 12 bolts, one with 3.23 peg leg and another with twin stripe and 3.73,,, both for $800.00.

 

At $100 each I would buy them. I appear to be a hoarder, though.

 

I bought the 10 bolt tonight, posi, 3.42 ring and pinion, measures 60.5 wheel to wheel, bolt in axles, brake hose bolt to a boss cast into the top and it has the 2 square lugs on the bottom,,,,,but,,, now I notice that the spring mounts are not hanging forward of the axle tube, they are on top of the tube just favoring the front of the tube by 3/4'' of an inch?? I have not had a chance to degunk it and get any numbers,, is this for an A body, or did I buy a freak?

 

You bought 1973-1977 - They are the most common A-body rears... They will not fit the 1972 and older.
Shoot some pictures of the rear we can ID it.
Will need the whole rear end shots with lower and upper control arm mounting areas in the pictures.
pictured below is a 1973-1977 rear




Jim
JD