Identifying Transmission

[dbdragracing]

I just bought a 1970 Ford Mustang Mach 1 351C. The door tag is gone due to a repaint. How can I tell which automatic transmission I have? Thanks.

 

[BullittStangV8]

You can look at it! seriously though, you can take a pic or describe it here and most people who have autos will let you know. Or there probably is a tag/stamped code on the tranny.

 

[dbdragracing]

Thanks I will look and maybe post some pics....I go pick the car up today!!!!

 

[StangDreamin']

If this helps.........

Here's a webpage that ID's tranny pan gaskets/filters..... compare the "shape" of the gasket and number of bolt holes to those attributes on your on your pan.

http://www.bulkpart.com/Merchant2/merchant.mvc?Screen=CTGY&Store_Code=2&Category_Code=Ford

Unless some major mods have been made; your choices should be limited to C4, C6 and FMX. Probably an FMX; although factory "big-powered" Cleveland 4V's sometimes came with a C6.

 

[dbdragracing]

Thanks...the vin# says the car is a 351C 4v and the owner said it was the original motor with some work done to it! Later.

 

[StangDreamin']

A factory 4V Cleveland from 1970? I'd lean a little more towards the C6.

FMX can be "built" for the HP/torque of an early 4V Cleve; but Ford already had the C6 by then........

 

[dbdragracing]

I used my Cars & Parts Magazine Catalog of Mustang ID Numbers 1964.5-93 book to read the vin# and it says the fifth digit in the vin indicated the motor. Mine is "M" and the book says thats a 351 CID V-8 (4V). I will know a 100% after the Marti report. Thanks.

 

[StangDreamin']

Well, all that's left is to (as Bullit said) crawl underneath and look!

 

[bnickel]

no factory c6 in 70 for the cleveland, either 2v or 4v, at least in the mustang. only trans it could have been would be the FMX. don't doubt the FMX though, it's a very stout trans, the big penalty with the FMX is weight because of the cast iron main case but the benefits are that it's tougher than a C4 and has about the same parasitic power loss as the c4, it's a little more but not much, it's also almost as tough as a C6 but has much less parasitic power loss than the C6 does, almost half. the only other big problem with the FMX is the difficulty in finding peformance parts for it, shift kits and convertors aren't too hard to find but still not as easy as the others.

however there is one place where you can most everything you need for a performance built FMX, should you decide to go that route;

www.broaderperformance.com

you can get stall convertors, Alto Red Line clutches and pretty much anything you'd ever need for an FMX. also check out the Ford trasnmission forum on network54.com

http://www.network54.com/Forum/260730/

you can learn anything and everything you ever wanted to know about the FMX or any other ford auto trans there.

 

[StangDreamin']

Bryan, I don't doubt the FMX at all! I've beaten the crap out of a couple of them; although apparently not enough to waste 2nd gear. Other than gasket leaks and one cracked pan (big rock in the wash that was our "driveway" after a storm); I have never had one let me down.

I'm thinking that, no matter what I do the the XR-7's Cleveland; the only reason the FMX alone would get yanked would be if I were to throw massive $$$ at a built AOD.

 

[bnickel]

Bryan, I don't doubt the FMX at all! I've beaten the crap out of a couple of them; although apparently not enough to waste 2nd gear. Other than gasket leaks and one cracked pan (big rock in the wash that was our "driveway" after a storm); I have never had one let me down.

I'm thinking that, no matter what I do the the XR-7's Cleveland; the only reason the FMX alone would get yanked would be if I were to throw massive $$$ at a built AOD.

i have wasted 2nd gear but that was due to the extra harsh shifts from the shift kit i had installed. it was a factory Ford shift kit and it was a stout SOB. we fixed that problem the last time i had it rebuilt by installing a steel "flex band" in place of the stock cast iron 2nd gear band. that is probably the only real weak point of the stock FMX. i've heard, though, that you can now use the 2nd gear band from an AOD and not have any problems. wish i could remember where i gleaned that little bit of knowledge so i could verify it's accuracy.

did you know that the AOD is actually based on the FMX? it's a fact, the inner workings of the AOD are absed on the FMX and many of the internal parts are interchangeable.

i actually have an AOD core that needs to be built but i decided against using it in the stang, though it will probably find it's way into the 69 coug

 

[D.Hearne]

Easiest way to Id these is just looking at what you've got. C-4 is all aluminum with a removeable bell. C-6 is all aluminum, but is all in one piece, no removeable bell. FMX has aluminum bell but iron case, bell bolts are external, like a manual trans, C-4's bell bolts are internal

 

[bnickel]

Easiest way to Id these is just looking at what you've got. C-4 is all aluminum with a removeable bell. C-6 is all aluminum, but is all in one piece, no removeable bell. FMX has aluminum bell but iron case, bell bolts are external, like a manual trans, C-4's bell bolts are internal

FMX also has an aluminum tail housing as well the aluminum bell housing, only the main case is cast iron.

 

[D.Hearne]

Right.