How do you tell the difference between c-6 and c-4 Ford transmission?

To distinguish between a C-6 and a C-4 Ford transmission, you can look at their physical size and design. The C-6 is larger and heavier, typically featuring a cast-iron case, while the C-4 is smaller and uses an aluminum case. Additionally, the C-6 has a deeper pan and usually has a separate bellhousing, whereas the C-4 has a more compact design. Checking the transmission's identification tag or number can also provide clarity on which model it is.