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Positraction Diff
Date: August 12, 2019 02:06PM

Are there any stamps on the Case of a Diff to determine Posi or non Posi?

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Re: Positraction Diff
Date: August 12, 2019 02:18PM

Okay i found it but they are very difficult to see
not easy to see them ..

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Re: Positraction Diff
Posted by: MattNall ()
Date: August 12, 2019 02:51PM

Easy TEST to see if it has one and IS WORKING


Rear wheels in air..

Rotate ONE wheel in any direction

OPEN Diff. other side goes reverse!

Posi and working... SAME rotation

MODERATOR
Sea Mountain, between Charleston Harbor and Coos Bay! SW Oregon Coast
Click HERE for My Website...Click HERE for My TechPages!
..............................110-PG.................................................Webered-Turbo

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Re: Positraction Diff
Posted by: solo2r ()
Date: August 12, 2019 07:26PM

Can not rely on the stamped letters, Do as Matt says or open top cover and do a visual

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Re: Positraction Diff
Posted by: JimBrandberg ()
Date: August 13, 2019 06:35AM

A positraction can turn into an open differential when worn. The posi parts can be in there but just not working.

Jim Brandberg
Isanti, MN
CorvairRepair.com



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Re: Positraction Diff
Date: August 13, 2019 01:40PM

Thanks for any information,Clarks has codes in his cataloque..

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Re: Positraction Diff
Posted by: vairchet ()
Date: August 13, 2019 09:18PM

Here's some information that could be useful (gleaned from Corvair Junkyard Primer):

Chet in Ramona

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Re: Positraction Diff
Date: August 14, 2019 01:57AM

This is what the factory stamping looks like:

Right side of Diff. forward of Axle yoke
The white paint is factory applied.
AD = 1966 Manual transmission Positraction
12 10 December 10, 1965 (They are not always so clearly Stamped...)

Additional details - 1966 Corsa Turbo Coupe
Engine build date T1209RL = December 09, 1965 RL= Turbo engine
Body Build Date 12C = December third week, 1965 in LOS Angeles,CA


Dan Davis ~ Pierce County, WA ~ CORSA Western Director + Corvairs NW + North Cascades Corvairs + Corvanatics
1966 Corsa Turbo coupe ~ ~ 1966 Corsa 140 Coupe ~ ~ 1965 Monza 140/4 Convertible Sierra Tan/Fawn ~ 1964 Monza Spyder Convertible ~ 1960 Monza Ermine White/Red PG ++ ~ 1965 Monza 140/4 CoupeEvening Orchid w/ ivory/black interior ~ 1962 Monza Wagon 102/4 ~ 1963 Rampside/Scamper ~ 1963 Red/Greenbrier ~ 1969 Ultra Van #468

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Re: Positraction Diff
Date: September 09, 2019 05:21PM

Thank you very much for these pics.

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Re: Positraction Diff
Posted by: joelsplace ()
Date: September 09, 2019 06:33PM

I've never seen one with the white paint or stamped that clearly. Nice!

Joel
Northlake, TX
5 Ultravans, Lost count at 100 Corvairs...

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Re: Positraction Diff
Posted by: texas yenko dude ()
Date: September 10, 2019 11:44AM

I’ve seen quite a few with lots of white paint and stamped well, but I’ve had a lot of posi’s over the years too.

Texas YENKO Dude
YS-070
YS-199
YS-320
Southeast of Disorder


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Re: Positraction Diff
Posted by: Caraholic4life ()
Date: September 10, 2019 02:07PM

joelsplace Wrote:
-------------------------------------------------------
> I've never seen one with the white paint or stamped that clearly. Nice!

Here you go Joel,
This is the one out of my '65 after I gave it an initial degreasing.
Once I got it clean enough to paint, I put some tape over the white so it would stand out after being painted.

1962 95 F.C. Van
1965 Monza Coupe
Westminster, Maryland

MID ENG enthusiast &
prior Kelmark owner.

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Re: Positraction Diff
Posted by: joelsplace ()
Date: September 10, 2019 02:33PM

Very interesting. I'll have to watch for the white paint. Is that one a posi? I went though the dozen '66 up transaxles I have easy access to a few months ago and none of them had the white paint. None were posi either.

Joel
Northlake, TX
5 Ultravans, Lost count at 100 Corvairs...




Edited 1 time(s). Last edit at 09/10/2019 02:34PM by joelsplace.

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Re: Positraction Diff
Posted by: Caraholic4life ()
Date: September 10, 2019 02:47PM

Yes, AD is a 3:55 Positraction code. AC would be 3:27 which I have in a 1966-69 as a spare I got many years ago when gathering parts to build another V8 car (Crown) but never got around to.
I sold the NOS Crown kit back in 2012.

1962 95 F.C. Van
1965 Monza Coupe
Westminster, Maryland

MID ENG enthusiast &
prior Kelmark owner.

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