What kind of transmission do I have?

I drive a 1994 Ford F-150, automatic with the overdrive swiched on/off with a on on the shifter. It is either a C4, C5, C6 ,AOD, or E4OD, but I have no Idea which one that means I have. I'm trying to adjust/fix my shift linkage and the repair manual has different sections for each type of automatic transmission.