ID: 812 Rear Diff-Thin P, Date Code K230
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From: Nashville TN
ID: 812 Rear Diff-Thin P, Date Code K230
New to the forum and have very much enjoyed all the posts I've read so far. Seems like a great place to trade info/knowledge and I appreciate what you guys have built here over the years. I am glad to be a part of it.
On to my question...
After reading as many posts as possible, (especially those by DZ AUTO, who is definitely the king-pin on the subject around these parts) I need some clarification on the date of my posi rear end. The 812 time period is '62-'64, but mine is stamped very clearly K230, which I read to be Nov. 23, 1960. This seems way too early for an 812 if they didn't start showing up in passenger cars until late '61. Is it too early or am I reading it wrong?
Thanks!
On to my question...
After reading as many posts as possible, (especially those by DZ AUTO, who is definitely the king-pin on the subject around these parts) I need some clarification on the date of my posi rear end. The 812 time period is '62-'64, but mine is stamped very clearly K230, which I read to be Nov. 23, 1960. This seems way too early for an 812 if they didn't start showing up in passenger cars until late '61. Is it too early or am I reading it wrong?
Thanks!
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FIRST, before we proceed any further, is the K230 STAMPED, or CAST (there is a major difference between stamped and cast numbers)?
Now, by 812, I presume you are referring to the CASTING number of 3789812, is that correct? If so, those were a mid-61 and later rear. The date of Nov 23, 1960 would have been in a mid-year model 61 car.
Over on the other side (passenger side) of the case should be 2 STAMPED letters and 3-4 stamped numbers together. The letters are the gear ratio code, and the numbers are the mo-day assembly date (there is no year in the stamped assembly date because the year is included in the CAST date). The assembly date will GENERALLY follow the cast date by 2-7days. For example, if your posi is a 3.70 ratio, and it was built 3 days after it was cast, then the STAMPED code could read something like this-AH1126.
Tom Parsons
Now, by 812, I presume you are referring to the CASTING number of 3789812, is that correct? If so, those were a mid-61 and later rear. The date of Nov 23, 1960 would have been in a mid-year model 61 car.
Over on the other side (passenger side) of the case should be 2 STAMPED letters and 3-4 stamped numbers together. The letters are the gear ratio code, and the numbers are the mo-day assembly date (there is no year in the stamped assembly date because the year is included in the CAST date). The assembly date will GENERALLY follow the cast date by 2-7days. For example, if your posi is a 3.70 ratio, and it was built 3 days after it was cast, then the STAMPED code could read something like this-AH1126.
Tom Parsons
