GM Posi vs. Eaton Posi
02-03-2014, 07:45 PM
#1
GM Posi vs. Eaton Posi
How does the Eaton Positraction compare to the original GM Positraction for use in a C-1?
02-03-2014, 07:54 PM
#2
Team Owner
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02-03-2014, 08:26 PM
#3
Thanks John. I'm going to 3.08s. Trying to decide between rebuilding the one I have for the '61 or going with a new Eaton unit.
02-03-2014, 08:45 PM
#4
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02-04-2014, 12:26 AM
#5
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2023 C1 of the Year Finalist - Modified
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As John mentioned, GM DID NOT make posi units for their vehicles.
Up through 64, DANA supplied posi units to GM and beginning with the 65 models, Posi units were supplied by Eaton.
For the early cars (57-62 Vettes, 57-64 pass cars), the DANA posi units are a good posi--------------------------BUT, the later (60-64) posi units are an upgraded improvement over the 57-59 units.
Thus, properly rebuild, the early DANA units are a very good posi---------------AS LONG AS THEY HAVE NOT BEEN SERIOUSLY ABUSED AND HAVE NO CRACKS ALONG THE BOLT HOLES FOR THE BOLTS WHICH ATTACH THE TWO HALVES TOGETHER!
FOR many YEARS, the original DANA posi units were all there was for the early Chevy rears. As good rebuildable units began to dry up, the prices began to skyrocket. Then along came Eaton with a posi unit for the early Chevy rears. THE EATON IS AN EXCELLENT POSI UNIT! Remember, Eaton posi units have been used in GM products for almost 50yrs. Also, they are rebuildable.
In addition to all the above, there is now another EXCELLENT posi unit available from NITRO. It is essentially a copy of the original DANA posi unit with some excellent upgrades.
Without hesitation, I can recommend either the Eaton or NITRO posi units and as I mentioned, if an original DANA posi is in good condition (requires COMPLETE teardown and close inspection of ALL internals and the case halves), it is a good posi unit for rebuilding.
Last, but not least, NITRO sells a kit of internal replacement parts for the original 60-64 DANA posi units. These internals for the original DANA units are a nice upgrade.
Here is a link to an article I put together a few years ago for converting a NON-posi rear to a posi. At the time, the conversion was with the Eaton unit. Since the NITRO has been introduced, I have updated the article with the information. So you will need to scorll all the way to the end to see the NITRO unit.
Here is the link.
http://www.chevytalk.org/fusionbb/sh...hp?tid/223912/
Up through 64, DANA supplied posi units to GM and beginning with the 65 models, Posi units were supplied by Eaton.
For the early cars (57-62 Vettes, 57-64 pass cars), the DANA posi units are a good posi--------------------------BUT, the later (60-64) posi units are an upgraded improvement over the 57-59 units.
Thus, properly rebuild, the early DANA units are a very good posi---------------AS LONG AS THEY HAVE NOT BEEN SERIOUSLY ABUSED AND HAVE NO CRACKS ALONG THE BOLT HOLES FOR THE BOLTS WHICH ATTACH THE TWO HALVES TOGETHER!
FOR many YEARS, the original DANA posi units were all there was for the early Chevy rears. As good rebuildable units began to dry up, the prices began to skyrocket. Then along came Eaton with a posi unit for the early Chevy rears. THE EATON IS AN EXCELLENT POSI UNIT! Remember, Eaton posi units have been used in GM products for almost 50yrs. Also, they are rebuildable.
In addition to all the above, there is now another EXCELLENT posi unit available from NITRO. It is essentially a copy of the original DANA posi unit with some excellent upgrades.
Without hesitation, I can recommend either the Eaton or NITRO posi units and as I mentioned, if an original DANA posi is in good condition (requires COMPLETE teardown and close inspection of ALL internals and the case halves), it is a good posi unit for rebuilding.
Last, but not least, NITRO sells a kit of internal replacement parts for the original 60-64 DANA posi units. These internals for the original DANA units are a nice upgrade.
Here is a link to an article I put together a few years ago for converting a NON-posi rear to a posi. At the time, the conversion was with the Eaton unit. Since the NITRO has been introduced, I have updated the article with the information. So you will need to scorll all the way to the end to see the NITRO unit.
Here is the link.
http://www.chevytalk.org/fusionbb/sh...hp?tid/223912/
Last edited by DZAUTO; 02-04-2014 at 09:16 AM.
02-04-2014, 01:10 AM
#6
John and Tom, I cant thank you enough. We are so lucky to have guys like you showing us the way. 