TR6 TR6 Transmission Identification ???

[adamaztr6]

Does anyone know how to identify the different types of Triumph transmissions? I just removed the alleged "stock" transmission from my 1971 TR6. The replacement clutch disc which I purchased has a different spline pattern. I went back to the parts store and verified the part as being correct. The numbers on the passenger side are 306812SM and V2947. Located forward of these numbers is WYF E359 which is printed upside down. On the driver side is STANPART, V2702 AND 305048. The transmission has 10 splines. I am not sure if the transmission is from another year TR6 or perhaps a different model entirely. Anyone transmission knowledgeable???

 

[BOXoROCKS]

If the new disc is fine spline chances are your parts guy got you a GT6 disc

 

[Alan_Myers]

Hi,

TR4 also use a different diameter input shaft/different clutch than TR4A/TR250 (I believe the latter used the same clutch as TR6).

Also look at your flywheel. The later cars use a diaphragm type clutch, about 8-1/2" in diameter, while the earlier cars used a little bit larger clutch with a series of springs around the outside. The mounting holes are different, so the flywheel would have to be drilled to accept an earlier type of clutch (since the 4 cylinder flywheel wouldn't interchange with a 6 cylinder flywheel).

As much as most of these old cars have been "messed with" over the years, all kinds of combinations show up!

The most important identification is the prefix of the serial number, on the lefthand side, stamped into the rear-facing side of the clutch actuating shaft boss. You'll usually see a four, five or six digit serial number and above or preceding it are the model identification letters, usually a combination of two letters. These can be hard to see and might be obscured by paint. From the numbers you reported, I don't think you've found the serial number and model identification, yet.

However, be warned that these identifiers have become increasingly meaningless as gearboxes got rebuilt and the innards were changed to accomodate different models. For example, my TR4 has a prefix "MB" gearbox, probably from one of the Triumph sedans originally, but rebuilt to TR4A specs. It should have a "CT" prefix. So, the info you find there might be less than helpful.

TR6 gearboxes were coded as follows according to the Moss catalog:
CD1 and up for 1968, 69 and part of 1970
CD20000 and up for 1970, 71 and 72
CC75001 and up for 1973, 74 and 74-1/2
CF12501UE for July 1974
CF35001UE for 1975
CF50001UE for 1976

Some more ideas.... Do you have the original clutch disc that came out of the car, that you could take with you to the parts store to compare? Or, do you have a clutch centering tool that you know matches the input shaft on the gearbox and might be taken to the store? As a last resort maybe take the gearbox itself with you, and try different TR-spec discs right at the store, to see what fits.

Alan

 

[adamaztr6]

I do have the clutch which came out with the transmission. A second trip to the parts store seems to be in order. As for the stamped number near the shaft boss I did not see any other numbers, however the body is still in need of cleaning. Thanks for the info.