find it hard to fathom why most hear dislike the ford auto trans.had a 57 merk 312 the trans was strong,they are easy to rebuild.lots of parts,tho front pumps are not always easy. the bw marine trans is similar,and a pre. post was comenting clutch plates from aods are useable and better.
with throtle pressure likage adjusted abit on the positive they will start in 1st gear. shift kit will also improve firmnes..
shifts into revers while moveing forward can crack the case. works ar rebuildable(later cooled via rad are best

No FMX was ever behind a Y block.  If I recall they came out in 67 or 68.. An FMX is basically an updated Cruis-o-Matic medium duty MX transmission that was used in many many Fords from about 58 to 66 or so. They are very similar to the Cruisomatic, with the FMX having the more modern gear selector and valve body and no rear pump. .. The conversion is pretty easy if you have a cruiso bellhousing. The FMX is a strong transmission and you will find them behind some stout Ford engines in Mustangs and Cougars and Torinos. Kind of between a C-4 and a C-6 strength wise in stock form.

Parts and rebuild kits are available..

In reading some of the excellent articles on this forum, I saw one re FMX transmissions and also one re C-4's
Is there or was there an FMX transmission that came behind a Y Block?
If so, what years? Also, is there anyone that would still rebuild them?
Just a few more of my dumb questions
Thanks Jim