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Old 02-24-2020, 10:21 PM
bcmiller bcmiller is offline
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Default Eaton Posi assembly date

All Eaton 12 bolt posi carriers received a stamped assembly date code. The code was in the format of letter / number / letter. It seems be be fairly well known that J was used for 1969. Do we know the letters used for 1965, 1966, 1967 and 1968?

Thanks in advance.
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Old 02-24-2020, 11:02 PM
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This help?
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Old 02-24-2020, 11:29 PM
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He is asking about the letters stamped on the outer edge of the ring gear flange on the Eaton Posi case. I've got cases that are stamped F, G, H and J. I think everyone knows that J is '69, but what are the others? The 12 bolt was produced from '65 to '72. Did these codes continue the same on the Eaton Posi case to '72?
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Old 02-25-2020, 12:21 AM
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Quote:
Originally Posted by bcmiller View Post
All Eaton 12 bolt posi carriers received a stamped assembly date code. The code was in the format of letter / number / letter. It seems be be fairly well known that J was used for 1969. Do we know the letters used for 1965, 1966, 1967 and 1968?

Thanks in advance.
I think they used letter A to k. For the year (did not use I ) J being 1969 you should be able to count back from there.
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Old 02-25-2020, 05:56 AM
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So you could have a JJ (October 1969)? By the chart letters are for months up to 1971
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Old 02-25-2020, 01:46 PM
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It would make sense that they didn’t use the letter I for year - but I swear I had one a few years ago with the year letter stamp being I. I could be wrong or suppose it could be later. Although they stopped being used in production in 1972, they were made much later.

Here is a later one. Year code JC - maybe 1993?
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Last edited by bcmiller; 02-25-2020 at 01:54 PM.
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Old 02-25-2020, 01:49 PM
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Quote:
Originally Posted by BCreekDave View Post
So you could have a JJ (October 1969)? By the chart letters are for months up to 1971
The format is letter number letter. Here is one stamped C 22 H from a 10 bolt 3 series posi.
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Last edited by bcmiller; 03-03-2020 at 10:02 PM. Reason: Update
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Old 02-25-2020, 10:27 PM
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So assuming that the E would be for the first year of production in '65, then F would be '66, G would be '67, H would be '68, J would be '69, K would be '70, L would be '71 and M would be '72? Can anyone verify this with something from '70 to '72?
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Old 02-26-2020, 01:58 AM
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Default 70 date

Here is jan. 22 assembled rear gear.
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Old 02-26-2020, 02:28 PM
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Thanks for posting that. The posi assembly date stamp is late 69, fits fine for a Jan 1970 axle assembly.

Would anyone have data from other years they would want to post from original axles?
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