I've actually been doing some research on this lately.. I've actually found several numbers that folks say are the TCC for our cars. Maybe someone can clear it up..
The most common GM part number I've found 8634960 and then there is 8639900 and 8639956 Also I hear you can use one for a 700R4 trans. You have to shim it a little. It's a "beefed up" one for the 200R4 but I have'nt found a GM number for that either. Funny part is turbo Buick guys from all over have used all of the GM part numbers I listed and they all seem to work
Where are the trans pro's!