# rear end question



## bluemist slate (Aug 30, 2021)

I have a 65 GTO with the standard 3.23 peg leg rear end. I want to convert it to limited slip but all I can find carrier wise is 3.36 and up gears. I would like to keep it a 3.23 but can't find a carrier. Then tonight read that my housing might not be able to take a gear ratio above a 3.31. Does anyone know if this is true or know if anyone makes a posi unit for a 3.23? 
Thanks


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## Roger that (Feb 6, 2010)

Safe-t-track had different carriers based on the gears ratios. There were 3 different versions:

2.56 to 2.73
2.93 to 3.23
3.36 to 4.33

Then there are 3 or more different carrier styles:

1964 to 1965 6 bolts holding case halves
1966 to 1969 8 bolts holding case halves

Most new limited slips for sale is probably going to be in the 3.36 to 4.33 range.

You might be able to find a carrier that already has safe-t-track in your gear range at Frank’s Pontiac parts or similar places.


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## armyadarkness (Dec 7, 2020)

I'm no expert on part numbers or applications, but I'd be very surprised if your housing wouldnt accept a larger ratio. I've swapped many carriers and gears, and in your case, I'd throw in an Auburn with 336. It's not worth mentioning the difference between it and 323


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## 67lemans (Oct 30, 2009)

Not sure if it is the same, but I had a 67 open with the 3.23 gear, and I got an Auburn Posi unit from Jegs.


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## bluemist slate (Aug 30, 2021)

67lemans,
So, you were able to keep the 3.23?


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## SLSTEVE (Dec 8, 2020)

bluemist slate said:


> I have a 65 GTO with the standard 3.23 peg leg rear end. I want to convert it to limited slip but all I can find carrier wise is 3.36 and up gears. I would like to keep it a 3.23 but can't find a carrier. Then tonight read that my housing might not be able to take a gear ratio above a 3.31. Does anyone know if this is true or know if anyone makes a posi unit for a 3.23?
> Thanks


Ran into a similar situation. Took my open rearend into the rebuilder and told him to rebuild it and make it a posi. He called me back and said it was a 2.93, so I said make it a 3.23 posi. Called me back again and said his supplier couldn’t get 3.23’s anymore, so I told him to make it a 3.55, if he could get a carrier for that. That’s what I ultimately ended up with. Hope it’s not too steep for what I want, but if it turns out to be, I’ll do something else.


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## 67lemans (Oct 30, 2009)

bluemist slate said:


> 67lemans,
> So, you were able to keep the 3.23?


Yes, I kept the same gear. I just checked Jegs and I don't see it there any longer, but I'm sure its around somewhere. I think this is it:
8 .2 10 Bolt Buick, Oldsmobile, Pontiac #542099 - drivetrain.com


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## 67lemans (Oct 30, 2009)

67lemans said:


> Yes, I kept the same gear. I just checked Jegs and I don't see it there any longer, but I'm sure its around somewhere. I think this is it:
> 8 .2 10 Bolt Buick, Oldsmobile, Pontiac #542099 - drivetrain.com


 Actually now that I look at it a little closer, I think that is the upgraded one. There is/was a standard posi (not high torque) that I used if you can find it.


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## bluemist slate (Aug 30, 2021)

Both Jegs and Summit have the carrier but I can't find need 3.23 gears.


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## 67lemans (Oct 30, 2009)

Unless I'm missing something, you are wanting to take the open diff out, and put this new posi diff in. (its a little more complicated than that, but not bad) You will bolt it up to the existing 3.23 gear that is in there, and shim it up snug if need be. You already have the gear you want in there. ( I took my rear axle houseing out to do all this and cleaned it up and replaced the seals - in the end I think it was easier and it was a good time to replace the bushings/control arms, but it can be done with the rear end in the car)


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## bluemist slate (Aug 30, 2021)

I plan to rebuild the whole rear diff and I don't plan on removing the rear end. I think it will be easier to build it on my lift than removing it. My suspension is done, so no new bushing needed. I'm a 26 year auto tech but don't have a lot of rear end experience but have help. My only real problem right now is finding the gears I want but I will go to a 3.36 gear in need be. After I have the parts my nightmare may begin.


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## armyadarkness (Dec 7, 2020)

As I already mentioned, Im not application expert... I can only help with the install


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## 67lemans (Oct 30, 2009)

Help is a good idea. Good luck with it and be safe! 

I was thinking you wanted to keep the 3.23 gear that was in there.

Before/After - notice the gear is the same.


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## armyadarkness (Dec 7, 2020)

According to this thread from last year, Auburn has a posi for 323








1967 gto BOP 8.2 POSI swap Help


Hello gear heads, I need some help... I have a 67 gto with an original BOP 8.2 open with 2.93 gears. I was told that all POSI must be used with 3.- - gears. What must I do to get some POSI going. I bought a rear end seal and bearing master kit from original parts place and currently have both...




www.gtoforum.com


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## armyadarkness (Dec 7, 2020)

Eaton and Auburn both have one.


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## bluemist slate (Aug 30, 2021)

67,
I do want to keep the 3.23 if I can but haven't found new 3.23 ring and pinion set yet. I have found the carrier that will take the 3.23 gears.
Thanks to everyone, all of you have been a big help!


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## 67lemans (Oct 30, 2009)

Why do you want a new ring and pinion set? Is there something wrong with the one that's in there?


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## armyadarkness (Dec 7, 2020)

Yes. Curious... Not following. My car had an open rear with the original 336's in it. I pulled the open carrier, took the 336's off it, put them on the new posi and reinstalled it all.


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## brydell (Oct 27, 2005)

I have a 2.56 Posi that was quiet when I pulled it to upgrade to a 3.55 Auburn. Unfortunately a 2.56 can only be upgraded to a 2.73. If anyone has an interest, let me know. The gears are clean with no chips, etc.


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