Originally Posted by Rhett
I think you hit the nail on the head.
When I browse thru a catalog of you-beaut accessories for this tranny, they only list the C4 (with variations). No hint of the elusive and mystic C5/C6/C9/C10/C-U-L8R.
Spot on, there are 3 versions of the C4 (windsor, 6cyl and cleveland), all have significant differences, but ALL are recorded by Ford as C4's, you just need to know what vehicle it came out of to know which one it is, or what the part number is on the box!
I have NEVER seen any official Ford document that mentions C9 or C10, only C4.
I have only ever seen C9/C10 in aftermarket books and publications, i believe the notation C9/10 was made up by tranny joints for easy reference however in Ford speak they are all C4's