66 Transmission Assembly code

[Donald H.]

I'm sure the information is in this forum, but I can't fine it. I'm trying to decode the assembly date on my transmission. I found the information for the 67s in Nolan Adams book, e.g. P for Muncie, then model year 7 then Month and day, and month was an Alpha character. The only thing I can find in his book is that the Model year was not used in 66.

My stamping looks like P0827, which I had assumed was August 27th. Was the month alpha character not used in 66?

Thanks,

Don

[Larry M.]

Re: 66 Transmission Assembly code

I'm sure the information is in this forum, but I can't fine it. I'm trying to decode the assembly date on my transmission. I found the information for the 67s in Nolan Adams book, e.g. P for Muncie, then model year 7 then Month and day, and month was an Alpha character. The only thing I can find in his book is that the Model year was not used in 66.

My stamping looks like P0827, which I had assumed was August 27th. Was the month alpha character not used in 66?

Thanks,

Don

Don:

Could the stamping be P0B27?? This decodes as Muncie (P), 1970 model year (0), February 27 (B27).

Larry

[Eric D.]

Re: 66 Transmission Assembly code

Thats the difference between 1966 and 1967 Muncie 3885010 main case casting build dates...

1966----P0827 uses only month and day( Aug. 27th 1965)
1967----P7M27 uses model year, month and day ( Aug. 27th 1966)

Hope this helps... Crash

[Donald H.]

Re: 66 Transmission Assembly code

Thats the difference between 1966 and 1967 Muncie 3885010 main case casting build dates...

1966----P0827 uses only month and day( Aug. 27th 1965)
1967----P7M27 uses model year, month and day ( Aug. 27th 1966)

Hope this helps... Crash

That makes sense. My transmission does have the VIN stamped and is correct for my car. Doesn't look like a re-stamp to me (picture attached). My issue is that my car is a July 66 build with a August 65 dated transmission.

transmission stamping2.jpg

[Matt L.]

Re: 66 Transmission Assembly code

That makes sense. My transmission does have the VIN stamped and is correct for my car. Doesn't look like a re-stamp to me (picture attached). My issue is that my car is a July 66 build with a August 65 dated transmission.

[ATTACH=CONFIG]47978[/ATTACH]

hi Donald,
viewing my date code i would say you are ok. mine is stamped P0208 for an april 66 build.


take care, Matt66 vette exhaust clamps 890.jpg

[Ronald L.]

Re: 66 Transmission Assembly code

Always great to see pics of Matt's car. Now how about a close up of that engine bay?

Don, Worse case of cases is that someone got a bare case and stamped the vin. You can find here on the forum an example of time travel where the VIN and P-date were stamped (trans assembled) a month before the main case was cast.

So what you can do so we can help you figure this out is get clean side picture of the main case, it has casting details there that are like reading your palm.

Then the tail shaft casting date details.
Then side cover casting date details.
Finally build date of the late 66 car is...


with good lighting, you can get these from underneath, no part removal required.

[Eric D.]

Re: 66 Transmission Assembly code

If you take into account that Don's Corvette was build at the end of the year, trans could have sat around in a corner, and finally used at the end of the model year...

I restored a trans for a customer, the trans was built 3rd week of Feb. but the car was built 3rd week of July...
As I was going thru his trans I found a main case with the same "P" number from the same assembly plant but 150,000+ VIN away, I asked him about what I found, he had window sticker, P.O.P. and build sheets for the car, thats when he told me the car was built at the end of the year, and they were using up all the left over parts so they didn't have to turn parts back into the parts system...

But like Ron said, some good clear pictures of the right side of the case showing the casting month and week dots and we'll know what you have...

Hope this helps... Crash

[Ronald L.]

Re: 66 Transmission Assembly code

These exections are just that, far and few between exceptions.

Pictures will make the base line, but 45 plus years later there are more re-stamp, or let's just say "stamped after the case left Muncie", than exceptions.

Eric I know you've seen them too, bad fonts etc, but the little tricky is that most of these come from service main cases made after the main sand cast patterns were changed to the 660 design.

What that means is there was a service set of patterns and non of those castings went through the P date process because they never got built into transmissions.

The interesting aspect about those is that they have some very tell-tale characteristics on the side of the case, and for one very knowledgeable, throw the red flag to look at VIN and P date for improper fonts, etc. And yes, some of those subtle quality control markings lacking on these 'post Muncie stamp jobs' are even more tell tale for the faked-up ones.

By the way, I can even show you how a specific pattern number degraded over the 66 model year.