FMX transmission

mikec35

Member
Jul 6, 2004
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I can't seem to find much info on fmx transmissions.. I have a 67 fb with a 69 351w and a fmx transmission. How good are the fmx's? I am restoring the car and the transmission is on the garage floor, it ran ok before taking it out but I am deciding if I should rebuild while it is out of the car. How much should I expect to pay for a rebuild? Thx
 
The FMX is tougher than the C-4. Drain the oil out and it'll still pull. It's a 1950's design, the AOD was based on it. Drawback is limited shift kits and stall converters, but they are out there, you just have to look a bit harder. If it was OK before, it's OK now. Maybe just change the front and rear seals while it's out.
 
they are heavy and performance parts aren't as easy to come by but they are available check out www.broaderperformance.com for some of the hard to find performance parts if you want to go that direction. back in the 70's the FMX was the trans to have for performance usage, especially in certain stock type classes, the reason is that it is much more heavy duty than a c4 but has less parasitic drag than a c6, it's actually on par with a c4 in that department. if it's a stock rebuild for the car then the FMX is more than up to the task in stock form. mine has a shift kit and stock convertor and works fine behind a mildly built 351w.