69 Th400 Help

[Brad H.]

Anyone have knowledge on where I might buy a 1969 TH400 Transmission and I'm hoping for recommendations for a good rebuilder.
Thanks again,
Brad

[Gary R.]

Re: 69 Th400 Help

Hi Brad,
If your TH400 is original to the car it should have a rivetted tag on the outside with the VIN. I would recommend rebuilding it if it is the original one. Just about any quality transmission shop can rebuild it stock or modified.
When I rebuilt my 72's TH400 I wanted it stronger then I really needed so I went with a 69 drum and 32 element 2nd clutch and the full B&M master kit. The only thing I don't like about it is the clunk I get in off idler use because of the new spring in the pump. Otherwise normal driving is the same but if I punch it then it will chirp 2nd & 3rd gear. I went with the FORD ATF too but don't think it's really necessary, I would have been fine the the GM ATF.

[Brad H.]

Re: 69 Th400 Help

Gary,
Unfortunately the transmission is the only major component not original to the car. It has no tag on it and has been rebuilt twice and still leaks. I don't believe the transmission is a 69 mode. I am hoping to find a 1969 build TH400 to have rebuilt.
Thanks for the info,
Brad

[Joe L.]

Re: 69 Th400 Help

Gary,
Unfortunately the transmission is the only major component not original to the car. It has no tag on it and has been rebuilt twice and still leaks. I don't believe the transmission is a 69 mode. I am hoping to find a 1969 build TH400 to have rebuilt.
Thanks for the info,
Brad

Brad------



You might want to contact a Corvette salvage yard like Contemporary Corvette in Bristol, PA.

By the way, the production codes found on the riveted-on sideplate for the 1969 Corvette THM 400 transmissions are as follows:

300 hp engine= "CK"

390 and 400 hp engines= "CL"

435/430 engines= "CY" ( you won't be finding one of these)

[Brad H.]

Re: 69 Th400 Help

Thanks Joe,
I will call them today. I really appreciate the code info!
Brad

[Don W.]

Re: 69 Th400 Help

Hi Joe...Is there any difference in the 3 transmissions, or is it just the letter codes? thanks...Don

[Terry M.]

Re: 69 Th400 Help

Some years back there was a Corvette Restorer story about the details of the CY transmission. IIRC a heavy walled case is among the features, but there is a longer list of springs and clutch packs that are different among the three transmissions.

[Joe L.]

Re: 69 Th400 Help

Hi Joe...Is there any difference in the 3 transmissions, or is it just the letter codes? thanks...Don

Don------


There are internal differences between the 3 different codes. And, there are differences between the plethora of other codes used for THM 400's in other car models and these 3. Some of the differences are quite minor; others not so minor.