GM Transmission Question

[Skywalker]

I have obtained after approx 33 years my birth motor and trans from my true 1970 Z28. I have many many years ago verified the motor to be the real deal. I have called several trans shops with my numbers off the passenger side inspection tag of my THM400 and no one can help identify it as a THM400 from a 1970 Z28. They say they don't have books that old. So, can any of you help? here is the two lines of info right off the trans.

506
70 CW 3935 lease:

 

[busabeast]

a 1970 camaro has a turbo hydra-matic 400 with the code "CW" so yes, it is an authentic trans for your car...
i work in transmissions and happen to have reference materials that go back that far- you lucky!

 

[rubbersidedown]

a 1970 camaro has a turbo hydra-matic 400 with the code "CW" so yes, it is an authentic trans for your car...
i work in transmissions and happen to have reference materials that go back that far- you lucky!

Say thank-you Skywalker,thats good lQQkin' out for a Bro.

RSD.

 

[Skywalker]

Well, I had hoped to find out that some serial number was on that trans some where and that it was specific to my specific VIN for my car. However, I much appreciate this info and I'm sure the Z28's had THM400's. Just wish I could tie this one to my VIN is at all possible. Many thanks........

a 1970 camaro has a turbo hydra-matic 400 with the code "CW" so yes, it is an authentic trans for your car...
i work in transmissions and happen to have reference materials that go back that far- you lucky!

 

[busabeast]

not really possible, the best you could do is say that it was originally installed in a 1970 camaro (Z28). that kind of info would be known only to the guys who put it together and then only if they were obssesive-compulsive. sorry i couldn't tell you what you wanted to hear...

 

[Skywalker]

Busabeast, you now have told me what I want to hear. Impossible, thus it is correct to say this is the actual birth transmission as I truely beleive it is. just no way to run a true serial number and so now I have the final answer and I'm good to go! Since I have known the motor/trans for at least the last 32 years and they have always been married up she must be. I'm now good to go and can ease my OCD...... LOL As always, the ORG has the answers to most everything and still the best site/family on the web. Everyone have a great weekend.....

not really possible, the best you could do is say that it was originally installed in a 1970 camaro (Z28). that kind of info would be known only to the guys who put it together and then only if they were obssesive-compulsive. sorry i couldn't tell you what you wanted to hear...

 

[busabeast]

glad i could help

 

[PocketRocket]

ahhhhh One of my favorite cars 70-72 camaro's... Nice

 

[Skywalker]

Couple of pics of course.

ahhhhh One of my favorite cars 70-72 camaro's... Nice

 

[dk55belair]

That set-up should have some kind of stall convertor, like 2500 or something from the factory. I think they were 11 inch.

My brothers roomie had a 70 1/2 but it was a 4 speed car, he changed the heads to some 202 valve, angle plugs and put a narrowed Dana with 4.88's under it and that car outran everything in town for about 10-15 years.

 

[dk55belair]

Little known fact for those of you(like me) that store useless knowledge.

In 1970 Chevy was late designing the Camaro body and they just sold 69's until this car came out, thus branding it the 1970 1/2 Camaro. The Z/28 had a 360 hp 350ci, and some magazines admit this rating was conservative and this was possibly the fastest production car built until recent years.

 

[Skywalker]

I sure love this old car. I have a 1500 B&M in there and does a pretty good job. This one came with 410's and still have the original numbers matching 12 bolt. had that rebuilt this past summer and she runs really well. now to do that original motor and tranny and get them back together after a long long seperation.

That set-up should have some kind of stall convertor, like 2500 or something from the factory. I think they were 11 inch.

My brothers roomie had a 70 1/2 but it was a 4 speed car, he changed the heads to some 202 valve, angle plugs and put a narrowed Dana with 4.88's under it and that car outran everything in town for about 10-15 years.

 

[Skywalker]

exactly right. They did a great job with the new LT1 and was a very strong motor in the day. Love the 69's and the DZ's as they would turn 10,000 RPM and anything would move with a motor turning that quick.

Little known fact for those of you(like me) that store useless knowledge.

In 1970 Chevy was late designing the Camaro body and they just sold 69's until this car came out, thus branding it the 1970 1/2 Camaro. The Z/28 had a 360 hp 350ci, and some magazines admit this rating was conservative and this was possibly the fastest production car built until recent years.

 

[Skywalker]

Well, I had put out several feelers when I posted here and had a good hit this morning from a friend via email. So, if anyone is interested this is the way the GM tag on the trans will be decoded. As well, my Z28 is a Jun build and thus the April Julian date is perfect a perfect timeframe to have slid that into the Z28 just two months after it's birthdate:

these #s you gave me were from actual tag riveted to side of trans right? "YES"
if so, these are TurboHydramatic/GM company #s

the 506 is upper right hand, and stamped. probably before this # was printed on tag
and no longer legible; so it goes:

70W 506

then stamped below is CW 70 3935

which is :

70 model yr
W engine code trans was to be mated with (ex. 69X = 1969RS Camaro, x=ZL1 eng.)
506 is julian date when trans made=
(1/1/70=366, so 506-366= 140; 04/20/1970; 20th April, 1970)

the 3935 is sequential production number from plant on assembly line.
(so they know which car they put this in- three thousandth, nine hundreth, thirty-fifth)

 

[busabeast]

sweet- i learned sumthin new!: