An old buddy of mine is cleaning out his shop, clearing out parts he will never need/use (he's 79 and is building his 'last car'- his words were "I've got one more car left in me then I'm done"- a '68 Cougar with a 500+ HP 429 and Custom built C-6, but that's another story). I went over to help out and ended up leaving with a spare C-6 and an FMX automatic. He said it would bolt up to my 302 but I've never heard of it. Can someone school me on this transmission?
FMX removable bellhousing , yes it will bolt up to small block with correct bellhousing . They were used behind 351 C engines . C6 all one piece unit , Van used C6 behind small block .
FMX was a good trans very dependable.came in cars light trucks.some were in performance models.only disadvantage is weight. they had cast iron main case with aluminum bell and tail.there are no modern shifters available for them rebuild kits are still around but you have to find and old ford mechanic to do it todays shops are clueless.
Just heavy. Found behind a lot of 351 Windsors, too. Stood up to a lot of large, slow, heavy 70s cruisers, but I ditched mine long ago for an AOD. Tranny guys, are there any FMX internals that are useful in AODs or other transmissions?
While I don't know a thing about them, I had one in a 49 ford pickup with a 302. I remember it'd squeak 2nd gear with the original 4.27 ratio rear end. I broke the rear axle twice....never broke that transmission.
The FMX was Ford's 'medium duty' trans, and basically just a continuation of the original three-speed Ford-o-matic and was the basis for the later AOD, although I don't know about parts interchange. Stronger than a C4, less parasitic horsepower loss than a C6. Very reliable, more complicated to work on, and as noted, heavier. With the right parts, a nice upgrade for a Y-block. Found behind some 302s, 352s, 351s (both Windsor and Cleveland's), 390s.
Fmx was the Ford variant of the cast iron small case Borg Warner. It differs in that the dipstick tube goes into the case in the FMX and into the side of the pan on the Borg Warner. There are very few parts that interchange internally. By the way Ford started using the Fmx in 1967. Before that, cast iron Borg Warner, small case, medium case, and large case.
I really liked FMX transmissions. I made a very good living rebuilding them when I worked at Ford dealers. The Trans is an obsolete carry over from a mixture of FX and MX transmissions of old with Ford. In the late 60's and 70's Ford used them as a stop gap when they could not keep up with C4 and C6 production. Although they used the same basic Raveneaux design, the FMX and AOD are completely different transmissions. They are heavy, leaky, and leak prone between the spit valve bodies due to the transfer tube and not a durable or serviceable as the newer C4 or C6. Like I said, I loved them because of their breakage. The car owners weren't happy, but my family benefited greatly. One of the best uses I have found for them is holding doors in place! You need a pretty strong wind force a door to move when held in place by an FMX. If you have nothing else to use, they are better than pushing, but not much. To those Ford engineers that designed and built it , I say thank you for providing for my family.
I am of the understanding that the FMX was introduced in the mid to late 60's as an improved CruisOmatic. Stronger than a C4, not sure about the C6. The FMX was used by other makers as well including Jaguar.
Cast iron case with alloy bellhousing and extension housing, manufactured from 1968 to 1979 and used down here until 1981 http://www.mustangandfords.com/how-to/drivetrain/mump-1203-understanding-automatic-transmissions/ http://www.charlietranny.com/FMX.htm http://www.roadkillcustoms.com/hot-...e-Database.asp?Transmission=FMX#axzz4GGHETKj5
I had an FMX (or FX or MX, which ever it really was) in my first car. A '65 Galaxie with 352. I enjoyed the rear pump that let you push start the car. Bill
Pretty much a bingo on that! in the early 70s used on 351 (C or W) 2 bl engines with the 351C-4V getting the C-6.
Gear train can be removed from rear of trans while still in car and rebuilt and reinstalled. Still won't work right. As stated they are a pain to work on .
I found this PDF on the web years ago and forget from where. So I can't give proper credit. But it's a nice story of the history of these transmissions. (hopefully the upload worked) -Bill
Wow, what a range of opinions; everything from "strong and durable" to utter POS. I'm really confused now as to whether to rebuild and run it or keep looking for a C-4.
C4 is durable enough if you aren't flogging it all the time. AOD is a better choice - especially ones that are beefed up with better valve and clutches and some later parts. Be realistic with yourself about how much you eventually want to spend on a transmission, how long you want it to last and whether you need the overdrive and rpm reduction at cruising speed that an AOD could offer. Or if you just want to drive the FMX until it poops on you. That could be a long time, and you could be saving money in the cookie jar for an upgrade later.
Trivia - I had a 65 Excalibur (12th made, so still on Stude frame with discs and original suspension). It had an L79 in it with an automatic trans. I let it sit in the garage for a few years while I was elsewhere, and when I got back and started it up, I backed out of the garage, put it into drive and it started out in low and then when it was time to shift up it dumped into reverse. Tried a couple of times, and then just drove it to the trans shop (in Seattle) in 1st gear. He said some corrosion in the interior had allowed a small hole to develop which, in turn, caused fluid pressure to shift the trans into reverse. It was an FMX trans, I asked him how that bolts up to Chev small block. He said it's the same tranny that Checker used in their sbc-powered cars because the taxi companies needed a strong transmission for not a lot of money, so they had adaptors made to accommodate the swap. Sorry I'm so long-winded on a subject that's not quite HAMB-friendly (although the car was fiberglass and aluminum and with that engine, it truly ran like a scalded cat).
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