1977 Thunderbird transmission question

My '77 Thunderbird's transmission is slipping, so of course I want to get it fixed as soonas possible. I've got a little problem though...the guy I usually go to for Transmission work doesn't work on FMX transmissions. So my question is...did all '77 Thunderbirds have FMX transmissions,and if not, how can I tell if mine has one or not.

thanks in advance,

Patrick

Well, it could've been a C4 or a C6, also. Still poking aroung to see if I can find the difference.

Well, about the only thing I found when I searched for "FMX vs C6" is that they are hard to find parts for, they are inferior to a C4 or C6, and they typically were found bolted to a 351. Oh, and they need a different flywheel/flexplate than a C6. So, unless you want to keep the FMX for sentimental purposes, drop in a C6 and be happy.

My '77 Thunderbird's transmission is slipping, so of course I want to get it fixed as soonas possible. I've got a little problem though...the guy I usually go to for Transmission work doesn't work on FMX transmissions. So my question is...did all '77 Thunderbirds have FMX transmissions,and if not, how can I tell if mine has one or not.

thanks in advance,

Patrick

To tell the difference between the C4,C6 & FMX
C4 has A bolt on Bell housing from inside the Bell housing
C6 Has A one piece housing, from Block to tail
FMX has A bolt on housing from outside the Bell Housing(4 external Bolts)

The C4 & FMX take less House Power to run than the C6 so unless you modified your engine greatly stay with the FMX or go with the C4.

I currently run A FMX in my 1990 T-bird Stock Car. The FMX has a cast iron case. Is heavier than the C4. But the FMX is stronger.

Good luck.