[brian12c]

Ive heard transmissions being called several differrent numbers, and i wondered if the numbers represented anything like the size or the gearing. ive hard everything from 350 to 700r4 so could someone fill me on on what these stand for? thanks bf

[pmeisel]

The older ones are just names, they may relate to something but not the gearing or anything useful. e.g. Ford C4 and C6 related to part numbers in the year of intro. C3 was a mini-C4, and C5 was an "improved" lock-up C4. A Turbo-Hydramatic 400 is bigger than a 350, -- but 400 of what?

The newer ones (4L60, 4R70W, 4R55) relate to torque capability, bigger is stronger, but I have to confess I have never learned exactly what the torque measurement referred to is.