Ok, I have an 83 Camaro and I picked up a 10 posi rear out of a 90 Transam.

Problem 1:
Someone tried to pull the posi out of the axle and screwed the cross pin bolt up and I can get it out. I was tossing around the idea of welding a bolt to the cross pin bolt to get it apart. Does anyone have any other ideas?

Problem 2:
The housing out of the T/A was pretty rusty and pitted, but in my search I found it to be a better housing than my rust free 83 unit. Is it worth it to try and use the newer housing?

Problem 3:
The gears in the 83 axle are 3.23 gears and the gears in the T/A rear are 2.73 gears. I would rather just throw the T/A rear in it but am afraid to loose performance by going so far up in ratio size. What do you all think?

Problem 4:
Is there a difference between the gears (ring size) of these two rears. Are they compatable to the point I can put the 3.23 gears in the newer housing?

My end state is that I want to retain the 3.23 gears, but I want the better housing, the posi, and the 28 spline axles. Is this possible?

 

1: The cross pin bolt normally breaks with about 1/2 thread left on the bolt. There is no torque on the bolt. I've usually had success removing the bolt with a dental pick. You may also be able to use a modified drift punch and tap it in to break off the last of the treads.

2: There were a few casting changes during the third gen production run but basically, it's still the same.

3: Judgment call. You 83 has a nicer ratio but the 90 will be on a 2 series carrier (see #4)

4: Ring gear size is different but the same. Your 83 is 7.5", the 90 is 7.625". Parts are completely interchangeable. Only the ring gear size was increased. Everything else is still the same. The 90 will have 28 spline axles however with the 2 series carrier, you're limited to gear choices without using special gear sets or spacers. If 3.23 gears are 2 series (I don't know for sure) then you can simply swap them onto the 90's carrier. If the 3.23 gears are 3 series, your best bet is to buy a 3 series, 28 spline posi (carrier) for a 7.5/7.625 diff and drop it in.

 

I have done a few sets of gears, but only had one broken cross pin bolt. It came out easy. So ideally I should be able to remove the head and then take the remainder of the bolt out?

 

You can't use the 3.23 gears in the TA rear end becasue the TA rear end has a 2 series differential and the 3.23 gears are 3 series gears. You can't swap the differential because of the different axle splines.

 

I though 3.23 gears can come on both a 3 series or a two series carrier. I wont know for sure until I pull the cover on the camaro rear end.

 

3.23 gears were only used on the 3 series differential.

 

Ahh I see, anyone want to buy the trans am rear? I would rather be a one legger than go that far up in gears.