As the post says, I was wondering if there is anyone who makes a 8.5" 10 bolt for our cars. I want to run a Torsen T2R diff and I heard this is the largest rear that they make these for. Anyone ever heard of one of these for our cars?

 

Dana did make an 8.5 10 bolt for 3rd gens which can also be used in a 4th gen but they don't make them anymore. I was just looking into this recently, it will work but good luck finding one from what I hear. Heres some info I found:

http://web.camaross.com/forums/showt...hreadid=116363

 

The Dana 8.5" is the Dana 44 diff. It's not the same as the 8.5" 10 bolt corporate GM diff.

 

No one has mass produced one for a 4th gen. The problem is that after you add up the cost of machine work, gears, posi/spool, fab work for spring perches, shocks mounts, control arm mounts and torque arm mounts your just about into the relm of buying a 12 bolt. If you can do all the fab work needed yourself, it can be done for a reasonable price. I had thought about it too and it has been discused here many times.

It just doesnt pay for anyone to go thru the hasel of producing one and end up costing $1500-$2000, depending on options, and just barely make a profit. You can buy a 12 bolt for $2k...


If you do it yourself... it can be done and will work.

 

I too desire the Dana 44 as you could get them with torque arm mounts. I know this because I bought a new one in the early 80's for my 350 Monza. Got it out of Texas someplace for about $800,
if I recall correctly... posi, 3.90 gear! Pretty close to 12 bolt in strength plus a little lighter, I believe.
Danm... I gotta find that Monza!!

 

Monza's used a torque tube not a torque arm. Same idea but different design.

Finding a Dana 44 for a 3rd or 4th gen isn't impossible but they're not cheap if you do find one. Unless one is almost given away, you could end up spending the same amount on a bolt in 12 bolt or 9".

 

I have a shop in Lansing MI. that ONLY does rear/front ends. They do them for EVERYTHING. They set up the 4.56 gear in my little 7-5/8" rearend and it lived to the tune of mid 1.5X sixtys.

I talked a little to them about making an 8.5" work but they thought welding the torque arm mounts to the center section
would be in a crucial area and probably would weaken the CC.

They advised me to use the 12 bolt as the mounts are cast into the CC, hence stronger.

I have concluded the only way to use a 10 bolt would be to switch over to a ladder bar system.