C6 or FMX?

[infantfinite86]

I have a '72 Ford Ranchero, and I don't know what tranny I have.
It's the a 3 speed on the column, but how do I tell if it's a C6 or a FMX?

[MrPbody]

FMX has an iron case, aluminum bellhousing and tailhousing. C-6 is an all-aluminum case with an integral bellhousing. If your 351C was a 2-bbl. stock, it's an FMX. 4-bbl. engines got the "baby" C-6.

Jim

[cowood]

although its true all fmx's do have iron cases.not all c-6's have integral bell housing , only those for f.e. . there are a few c-4's that came behind clevelands w/removable bell ,easy tell-tell this c-4 dipstick tube is threaded.this tranny will bolt up to a 460,& w/ some beefing up is just as tough and a whole lot smoother than a c-6 and has less horsepower loss. i have seen this c-4 hold up to 1000h.p . for years on end without fail.

[MrPbody]

Cowood,
I've never seen a C-6 that wasn't an "integral bellhousing". Please advise, what car/truck did they come in, and behind what engine?

I've also never seen a C-4 behind anything bigger than a 302. All the Cleveland Mach 1s were FMX with the 2-bbl. and the "baby" C-6 behind 4-bbl. engines.
The bellhousing that fits a smallblock will not fit the Lima OR FE blocks, nor the "M" blocks.

I'm real curious your information source. Built LOTS of Fords over the years. Never see any of the combos you talk about.

Jim

[cowood]

the c-4's i'm referring to, personaly i have only seen in lincolns or ltd's and big bodied merc.s of the early 70's behind 351 m.
as for the c-6 i have a 75 f-150 460 in my yard w/ detatchable bell housing. granted it was special ordered w/ towing package and shifts alittle harder than most but it's still just a c-6. as far as i know the tow pkg. was just a heavy duty bumper & h.d.rear springs and 4-barrel carb.
i am also curious about what you are calling the baby c-6, what are its characteristics?

[MrPbody]

The ones you have behind the M engines are FMX, I'm quite sure... (nothing is EVER "in stone" when it comes to what came with what, so don't quote me...) A good friend/customer has two '79 F-150s . One is a 351M and the other is a 400. The 400 has the extended cab and long bed, no tow pack, C-6, no doubt. The other has the tow pack, standard cab, long bed. Also a C-6, no doubt.

Funny, but just a couple of days ago, I caught a blurb from an otherwise very knowledgeable guy (on another site) stating the M engines are junk with a capital "J". I couldn't disagree more! He was refering to all the head cracking and overheating problems they had when "young". Lance's (my friend referenced above) trucks will pull a house down, and get decent fuel economy for their size/weight (about 14 MPG with a load). No heating, no oil burning, no nuthin' but good... We built both engines here. One has over 90K on it since the rebuild. I suspect, their emmission controls and tuning to make the things run with the old technology, was the main reason for the massive problems. With today's technology and techniques, along with modern cam profiles and cooling systems, they are GREAT engines.
Sorry, didn't mean to get off on a tangent here, just found it interesting...

The "baby C-6" was the nickname for the small block version that came behind 351C 4-bbl. engines. That was the only application until it re-appeared in the late '70s in vans and pickups behind 302s and 351Ws with heavy duty packages. At one time, it was "prized". Anymore, it isn't very hard to come by.

I have a very close friend that's a transmission man from the "old" days. I'll talk to him and see what might be there. You got my curiosity up now!

Happy New Year!!!

Jim

[cowood]

ya know were starting to clutter this guys thread but im telling you these c-4's do exist absolutely,positively . i have beento the junk yard myself and pulled them . its a racer dream . my buddy who is a master machinist / racer figured out this trick .you take a c-4 any c-4 for that matter has 4 clutches inside c-6's have 6 clutches inside hence the name.machine out the housing to make room for another clutch effectively turning a c-4 into a bulletproof c-5,with a few other minor modifications that im not at liberty to disclose.overall weight and reciprocating weight of the trans. is significantly dropped= faster e.t.

351 m has same bell housing as 460,429,it is definitely a c-4 with a threaded dipstick tube. the bell housing is the real gold of the package . because it allows you to put a lighter trans. behind a big block

[MrPbody]

Thanks. If you had a pic or two, I would appreciate it.

Jim

[stuarta]

C6 transmissions did not have a detacheable bell housing.

C4 and the MX series are the only ones.

[zx2guy]

just curious about this... and not to detract from infantfinite86's but i thought that this could help me too. i have a 73 mercury cougar... 2v 351 C... and i was wondering too what my tranny is... i do have the code off of the door. its an X... and if anyone knows too... my rear diff code is a 2... and if anyone knows if thats the ford 9" i would appreciate help

and one side note which tranny is the strongest... or can be built stronger... i plan to make a screamer out of my car and i dont want to break anything.

[stuarta]

Originally Posted by cowood

ya know were starting to clutter this guys thread but im telling you these c-4's do exist absolutely,positively . i have beento the junk yard myself and pulled them . its a racer dream . my buddy who is a master machinist / racer figured out this trick .you take a c-4 any c-4 for that matter has 4 clutches inside c-6's have 6 clutches inside hence the name.machine out the housing to make room for another clutch effectively turning a c-4 into a bulletproof c-5,with a few other minor modifications that im not at liberty to disclose.overall weight and reciprocating weight of the trans. is significantly dropped= faster e.t.

351 m has same bell housing as 460,429,it is definitely a c-4 with a threaded dipstick tube. the bell housing is the real gold of the package . because it allows you to put a lighter trans. behind a big block

http://www.bulkpart.com/Merchant2/me...gory_Code=Ford

Yes a C4 has a removeable bell housing.
But there is no way possible of turning a C4 into a C6 or any other C.
I don't care if your name is Merlin.
If you are adding more clutches you are merely beefing the transmission up.
That part ain't rocket science.

A c4 and a C6 are two different transmissions.
In fact you could put an complete c4 inside a C6.
Yes you can bolt C4 to a very large engine.
back to the drawing board my friend.

[infantfinite86]

Wow, this turned into nice thread.
I took a look over my Door Data Plate (I feel like an idiot for not doing that in the first place), and my transmission code is "W". Dearborn Classics has a nice breakdown of the Data Codes, but naturally, it didn't tell what a "W" was for 1972. "W" was a C4 in previous years, and there wasn't a single entry for a FMX ever using a "W", but instead using an "X" from 70-72, so I decided to throw in that tidbit to you guys too. Can anyone name a site that I could go to that has a more extensive guide to the Door Data and what each code signifies?
Oh, and while I'm on the subject of trannsmissions, can anyone tell me if the 351W and 351C have the same trannsmission bolt pattern? Or if they can tell me where I can find out? The reason I ask is that I can't find a company that makes a kit to mount a T-56 tranny to a 351C, but they do have them for the 351W...And I'm VERY much hoping that it will work, otherwise I'll have to find a machine shop that can modify the bellhousing for me.

[stuarta]

Can you post the entire serial number?

[MrPbody]

Yes, Cleveland and Windsor share the bellhousing bolt pattern, along with 289 (late) and 302 (and 240/300-6 of all things...).

Look at the case. If it's iron , with aluminum bell and tail, FMX, no doubt. If it's all aluminum, and has an integral bellhousing (not detatchable), C-6. All aluminum, and bellhousing can be removed, if the bolts holding it on go through the pump housing, C-4. If the bolts do NOT go through the pump housing, C-5.

FWIW, EVERY 351C 2-bbl. I've ever seen with an automatic, was FMX. Every 351C 4-bbl. was C-6. Those are cars I HAVE SEEN. I won't dispute oddballs. I've seen some pretty strange stuff over the years, so very little surprises me anymore...

Jim

[infantfinite86]

VIN: 2A47H319678

Body: 97D
Color: 4C
Trim: UAA
Trans: W
Axle: 6
DSO: 71

I found a site that had the trans code for 72, mine's a C4, which is cool, because I want to throw a Hurst Quarter stick on it, but I only found them for C4's and C6's. At least I finally know what I have.

And MrPbody, you are now officially my hero. I'm so ecstatic about that information that I could do a lil jig right now, but I'm at work, so I'll refrain.

Thank you VERY much, all of you guys. I'm gonna have to come back to you guys for more advice and questions when they come up.