[dld]

Originally Posted by 1oldgoat

The guy with the axle is checking the casting and date codes for me. It came out of his brothers car years ago. He says he has the PHS report that shows it was a tri power, 4spd, 3.90 car. So, I'm hoping it's real. My car was an April build so maybe I'll get lucky. Thanks for your help. I'm pretty fair with the 68-72 GTO's but not so much on the older ones.

guys that post hear know everything

[1oldgoat]

The code was 9783393 which I think is a 66 code.

[dld]

Originally Posted by 1oldgoat

The code was 9783393 which I think is a 66 code.

the 65 rear is 54.5 inside of back plate flange to flange

the date code on housing is a way to tell year of casting

i don't know casting # for 66 . ask on 66 67 forum if need

if you go to 64 65 forum do a search for (65 rear ) we have talked alot about this

[Slob4]

While searching for a 3.23 65 gto rear I found a 3.90 rear listed on Craigslist in Indianapolis...I would check it out asap!!! Good luck and let me know how it goes

[Slob4]

Pm sent

[Tom Vaught]

As was posted:

64-65 Rear Axle Housing is 'shorter' side to side vs the later rear axles.
Pontiac axles have bearing retention vs Chebbys do not (unless using disc brakes on the rear).

3.36 Gear is the lowest numrical ratio posi that is same as used with 4.33 and 3.90 gear sets.

I have no use for spacers in a performance application but some have drag raced with them.

The rear gears need to have an expert set them up with the proper tools. The expert may be another racer vs a business.

Custom gear sets that allow a different series gear ratio on a posi unit needs to be very carefully checked on a true Pontiac posi unit. Chebby and Pontiac units are not the same.

Tom V.

[1oldgoat]

Originally Posted by Slob4

Pm sent

Thanks for the heads up. That's the same one another PY member told me about. Unfortunately it a 66-67 by the casting number. It would make a great axle for someone but I'm still holding out to find a correct 65 axle.

[Slob4]

I will keep looking!!

I am in the same boat - looking for a YF 65 3.23 rear for my 65!!

I, just like you, want the correct rear for my car

[1oldgoat]

Originally Posted by Slob4

I will keep looking!!

I am in the same boat - looking for a YF 65 3.23 rear for my 65!!

I, just like you, want the correct rear for my car

If I find a correct one for mine, the 3.23 that's currently in my car will be available.