I have an FMX that needs rebuilt. WOndering if anyone has ever had one of these things apart and rebuilt successfully. I know nothing about them or ever had one apart. Should i attempt or bite the bullet and leave it to a tranny shop?
I have really good mechanical skills. I just dont want to get into something that i cant finish and then show up at a tranny shop with boxes of parts. Its one of those things i dont know what to expect when i start tearing it down.
As a Transmission Tech at a Ford dealer for many years I would not consider the FMX trans unless I had to. The FMX had many problems during its use the most common of which is the transfer tubes coming loose and falling into the pan causing total loss of operation. The C4 is the perfect Trans for any Mustang and parts are readily available from stock to full race. My advise is to scrap the FMX and get a C4.
Have done many FMX transmissions, here, too. I do like the C4 and C6 better, but for a restoration, sometmes only an FMX will do. They are a bit different, ie. using a Ravineaux planetary set instead of a Simpson and you sort of disassemble and reassemble from both ends. Just be sure you get a good manual and a Transgo Shift Kit. There are easy fixes for the transfer tube issue so I say have at it. If you have any questions please feel free to ask.
Need to check if you need any special tools for FMX. C4 you don't but I believe I've heard FMXs are harder to rebuild. A friend (hydraulics mechanic) and I rebuilt a c4. Not too complicted but a lot of parts - took a few weekends since we were new to this. Ended up burning it up the first time I drove. Ended up getting one from TCI from Summit. I won't venture down path of rebuilding anymore.
I went through the same dilemma a few weeks ago. I searched high and low for a decent manual for the FMX. Lots of people recommend finding the ATSG manual if possible. However, I looked for hours online and never came up with anything for an FMX. There are tons of manuals and information out there for building a C4 and C6. If there's any manual that deals specifically with an FMX, then I couldn't find it.
FMX's were notorious for wanting to start out in 2nd gear, and refusing to downshift back into first unless you stomped the gas. I'm a professional mechanic, and after making a few calls and talking with several fellow mechanics that worked on these cars when they were new, I found that very few people had good things to say about the FMX. After hearing that, I had a local shop build mine. I just didn't want to mess with it, especially when so many professionals don't care for them. Like someone else mentioned, though, an FMX was my only choice for my '69 Mach 1. We'll see how it performs when I get it back from the rebuilder.
imo on something like this if you have to ask how then dont do it.
too much of a hassle, to heavy and too much of a PIA to pull it, work on it then reinstall it only to find out somethings messed up.
you can save some $$$$ if you do the bull work and haul the tranny over to a decent shop and have them do it., but then again you may have warrenty issues if something is wrong & theyll blame it on you.
somethings in life will just cost ya no matter what.
as far as relialbity mines been running since new with no probs and only had it overhauled once in back 1991 at the 100,000 mile mark. the job was only $400 back then lol so $500 today sounds like a good deal if theyre really doing the whole thing and not just seals.
FireMike, don't do it. The FMX is not worth rebuilding. Neither is the C4 or the C6, unless you are doing a drag race only deal. Drive the FMX untill it pukes and then set it aside for the chance you'll sell the car to an originality freak. To drive around and enjoy the car, get yourself an AOD and put that in. It fits easily, nobody can see it without crawling under the car, and you get overdrive. Whats not to like ? there are thousands of AODs out there just waiting for something to do......usually for less $ than it costs to fix the older 3 speed. LSG