fmx small case cruise o matic

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What is a "FMX" transmission????

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Can someone please tell me a little about the FMX transmission? I believe my '69 has this transmission. What are the weak and strong points? Is it a good or bad transmission to have? My car had a 351 2V. Thanks' Randy  

It is the combination of the FX and MX cast iron Cruise-o-Matic transmissions into one case! The small case with the big guts installed in it.  

Does this make it more reliable.  

The FMX is a step between the C4 and C6. They're fairly reliable transmissions, just not a lot of support aftermarket wise for them. Also, with a cast iron main case, they're heavier than a C4.  

The FMX often gets a bad wrap because of its weight, and it's hard to find people that know the right way to work on them. If put together right, they're actually a solid transmission. The downsides are they're heavy, a little more difficult to get parts for than a C4 or C6, and they're expensive to work on. Upsides are they're tough, and have a smooth shift.  

I happened upon once by chance, rebuilt too. I called every auto trans shop local to me and tried to see if they'd take it as a core. Everyone told me the same story...didn't want the boat anchor.  

There's a place in OKC that's very knowledgeable about them, and they rebuilt one for a car I used to have. I even had them do a few things to it, and we put a stall in it, but it was expensive. So expensive it wasn't worth it.  

A big heavy tranny..but strong as hell, I have one in my 72 Mach all I ever had to do to it was change the seals after it sat for 8 years, after 38 years it is still going strong, never misses a beat. And by the way I was never easy on it.  

I don't think it's so much the FMX is a bad transmission, it's that the C4 and C6 are such good ones. There are folk building the light and power efficient C4 to handle ridiculous power reliably, for not crazy money. John Edit: Just to add that if the C6 didn't exist, there would be a ton more development and performance parts available for the FMX. Of course, this wouldn't help the weight unless an aftermarket FMX aluminum case was made...  

If I had thought about the reliability part of my question I could have answered it my self. My car has almost 200k miles and the transmission is still going strong. Thanks for all of the input. Now I know.  

the C4 takes 28 hp to operate , the C6 uses up 55 hp , the FMX 25 hp and is way stronger than the plastic explosive C4 ! i use to out run the cops on my FMX !  

The way I tell them apart is that the FMX bolts on to the bellhousing like a 4-speed does. You can pull it out leaving the bellhouse and torque converter in place. I've had several FMX's over the years. They are tough--the one in my '69 years ago shifted so strong that it easily barked the tires into second. I also learned they are very sensitive to fluid levels. Get a quart low, pull up to a stop sign, and vroom vroom--seems like you are in neutral. They don't like to be run low. Never had that bad of a problem with my C-4's and I have had some leaky ones!  

Had one in my 72 Mach, swapped it for a modified AOD (4.11 rear) and the FMX went in the trash can.  

the AOD is based on the FMX. i use to out ranned the police on my FMX or wuz it BMX , maybe AMX ?  

"the AOD is based on the FMX". This seems a popular thing to say on the net, I wonder who figured this out. A friend is a semi-retired transmission rebuilder with almost 50 years of experience. He can rebuild an AOD with his eyes closed and still remembers tricks to rebuilding Ford-O-Matics. I asked him about this once and he stated that the FMX and AOD's had absolutely nothing in common internally in either parts or design. I've only dabbled a bit in rebuilding an AOD or two but in looking at the manuals and tearing down an FMX, I have to agree. About old transmissions have things in common like drums, bands, governors, etc. , but I haven't seen anything in an FMX to indicate that the AOD design was based on it anymore than the AOD was based on a Chrysler 727 TorqueFlite or something. Just curious, as I keep hearing this and personally see no connection in lineage at all between the FMX and AOD. Perhaps someone knows more about this in particular?  

The AOD gear train design was based on the gear train of the FMX/Cruise-O-Matic transmission which (in one form or another) has been part of Ford's automatic transmission history for decades. This gear train incorporates a compound (six-pinion) planetary gear unit, utilizing one planetary carrier with a set of short and long pinions, rather than two or three single planet carriers. This design was probably used because of the minimal changes needed to "add" overdrive to it. In fact, the FMX, AOD and AOD-E/4R70W are the only modern Ford transmissions which share the compound planetary design. Click to expand...

So the AOD is attributed to FMX heritage merely because they share the same style of planetaries? Good enough, I learned something today. Thank you.  

If I had one that needed rebuilding I would go to a C4 instead. Broader Performance has really good prices and they know what they are doing.  

I had one in a 68 Galaxie I had. Couldnt kill it. This was the same car that the front brake line rubbed through. I was on a road trip and didn't have the stuff to fix it on the road (this was in '86). When I got where I was going, I was doing 10 mph when I had to stop or run into something. Put it in PARK! Hell of a stop. Next day fixed the brake line and drove the car home. Not sure how that would operation would fair on a C4 or today's modern transmissions, but that thing was indestructible. And of course, in a galaxie, what's another couple hundred pounds. 0-70 in about 6 miles, but it was a smooth ride.  

I had one in a '69 Cougar XR-7. Good tranny for what it was in. No complaints. They can be built to be strong... for a slushbox.  

Hey, sportsroof69, I live in Moore, Ok and I am looking for a 65-70 fastback for sale. Preferably 69. Do you know anyone selling? You can call me if you'd like or email. Thanks -Chad 4O5-397-O233 or [email protected]  

Question Wich headers can i use in a 351c 2v with fmx transmision??  

Beats a C6 any day! Had a 68 XL with a 390 2bbl Y code engine. Not a torque monster but it did OK! I trashed 3 C6's until I finally pulled one out of a police car. It was still in it when I sold it, but the fellow I sold it to told me 6 months later he had to rebuild it again! Just bought a 68 LTD with the same engine and a FMX transmission and so far so good! Had real good luck with the C6 in my 77 F150 with a 400 Police Interceptor I put in, but I'm always scared when I see a C6!  

I'm new to this forum. So I'm working on a 1969 Mustang Mach 1 351W 4v. Got a Marti Report on it and it's supposed to have a FMX transmission. I actually picked up a FMX core off of craigslist locally that was removed from a 1969 Mustang 351W 2V. I'm wondering what the difference is between a FMX that would go into a the 2 set ups. I called a local transmission place that sells master rebuild kits and so on and the rep said that there was no difference in the kit sold for either motor set up. Why would there be a part number tag that is different from a 351W 4v VS a 351W 2v??? I have a good friend who is going to rebuild the FMX, but I have to find out the difference before he gets started. I've had someone suggest that shift points may be different or maybe the springs in the governor may be different or maybe the shift linkage on the side of the FMX may be different between the 2v vs the 4v 351. Any help here would be great. Also, I'm going fairly stock with the 351W 4v, but it will be pushing more HP that could be as much as 100hp more than the stock 290hp. Can I just have the FMX rebuilt with a standard master rebuild kit and the torque converter stock also? There doesn't appear to be much out there for upgrades and torque converter upgrades appear to be pretty spendy. Any help would be appreciated here. Thanks!  

1969Mach1Sean said: I'm new to this forum. So I'm working on a 1969 Mustang Mach 1 351W 4v. Got a Marti Report on it and it's supposed to have a FMX transmission. I actually picked up a FMX core off of craigslist locally that was removed from a 1969 Mustang 351W 2V. I'm wondering what the difference is between a FMX that would go into a the 2 set ups. Click to expand...

I have a 1973 mustang fastback with an FMX transmission. Reverse gear is giving me some problems. I have been debating changing it to a C-6. I would appreciate any thoughts on doing the change.  

Lot of folks with exactly one post in this thread. But anyway, you have to change quite a bit of stuff to fit a C6. Also it's bigger and heavier, more suited for a truck, RV, big block Lincoln, stuff like that. Not a lot of folks still out there tha tknow how to fix MX's and FMX's but they're still out there and it's not an expensive transmission to repair as those things. If you want to throw the baby out with the bathwater, then a C4 is a better choice. You can build one how you want and a modified will handle the power a stock C6 can while being a lot smaller, lighter, and more efficient. If you decide you need overdrive than an AOD or 4R70W swap is awful nice cruising on interstates.  

I was told you could put another gear in a 3 speed FMX. I don't know much about this so forgive me if this is a dumb question. Thank you!  

Another "one hit poster! No, sorry, you cannot. You can buy a pretty expensive "GearVendors Overdrive" and add an extra gear to many kinds of transmissions but for most it's not practical or worth the expense.  

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Ford Cruise-O-Matic MX Early Medium Automatic Transmission Master Overhaul Kit

Part Number: COM-M-MK

Product Type: Automatic Transmission Overhaul Kit

Vendor: Rigid Axle

• Product Description

OEM Quality Automatic Transmission  Rebuild Kit

Kit contents:.

Paper and Rubber Kit

Metal Clad Seals

Friction Clutches

• Master Overhaul Rebuild Kit without Steels
• Fits 1955-1966, Cruise O Matic "Medium Case" MX
• Used in Ford, Lincoln and Mercury
• 3 Speed Automatic Transmission
• small case (from 1951 to 1966) Not included
• medium case (from 1955 to 1966) this Kit is for this variation.
• FMX (from 1967 to 1979) Not Included

Transtar Industries

• Transtar Industries, Inc. is the leading worldwide distributor of transmission-related products, automotive specialty repair and refinishing products, and high-performance parts and accessories. Among its transmission-related offerings are automatic and standard transmission and transfer case units, kits and components, as well as other driveline and powertrain products.
• With more than 50 shipping warehouse locations in the U.S., Puerto Rico, and Canada, Transtar Industries serves independent and franchise transmission repair shops, automotive general repair businesses, production rebuilders, and resellers throughout North America. Transtar's International Division serves a global network of Aftermarket automotive distributors in more than 80 countries around the world.
• Transtar Industries, Inc., headquartered in Cleveland, Ohio, was founded in 1975. Their team of outstanding professionals is dedicated to providing customers with responsive service, expert product knowledge and support , and on-time delivery. 

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332-428 Ford FE Engine Forum

• 332-428 Ford FE Engine Forum > General Discussion > 332-428 Ford FE Engine Forum >

Cruise-O-Matic question

Post Jul 31, 2011 #1 2011-07-31T17:47+00:00

Post Jul 31, 2011 #2 2011-07-31T20:38+00:00

Post Jul 31, 2011 #3 2011-07-31T21:14+00:00

Why is a lack of 3rd gear such a common trouble on a Cruise-O-Matic? After reading about a C6 swap into my Galaxie it seems most people do the swap because of that exact problem. Mine, for example, only shifts into third after about ten minutes of driving when it's had plenty of time to warm up. This is just out of curiosity as I have no intentions of rebuilding mine after I replace it with my C6. I just want to know why this is so common... Michael Stanford (San Marcos, TX) 1963 1/2 Ford Galaxie 500XL - 390 / Cruise-O-Matic (Project of ten years and going) 2004 Ford Ranger Edge - 2wd truck that gets treated like it's 4wd 2011 Jayco Jay Flight 22FB (Home sweet home!)

Post Jul 31, 2011 #4 2011-07-31T23:28+00:00

Post Aug 01, 2011 #5 2011-08-01T00:45+00:00

http://en.wikipedia.org/wiki/Cruise-O-Matic

Post Aug 01, 2011 #6 2011-08-01T03:56+00:00

Post Aug 01, 2011 #7 2011-08-01T05:03+00:00

Post Aug 01, 2011 #8 2011-08-01T09:27+00:00

Post Aug 01, 2011 #9 2011-08-01T16:35+00:00

I thought that a 289 full-size from '67 would have a C4, not a Cruiso. I have a 'small case' cruiso that came stock in my 352-powered galaxie. With a stock rebuild and a modified valve body by Jay Broader it works pretty well. I still really dislike not being able to select between 1st and 2nd when manually shifting, but I don't know of a way to convert the trans from 'green dot' pattern to 'select shift' pattern...

Post Aug 01, 2011 #10 2011-08-01T18:33+00:00

Post Aug 01, 2011 #11 2011-08-01T18:35+00:00

Post Aug 01, 2011 #12 2011-08-01T19:20+00:00

What I thought was going to be a simple response ended up being far from it. haha I'm not complaining though. I love learning about this kind of stuff as you never know when it will come in handy (even though it took me several reads to fully comprehend all of the differences stated in those 8 edits). I definitely appreciate all of the responses. I'm always reading about the various engines offered by FoMoCo in the '60s but the transmissions have always taken a backseat in my interests. Now, after further reading I'm curious to see whether the tranny in my Galaxie is an MX or an FX. I have to admit, no matter which one it is I'm really impressed with it as it's withstood some abuse from my heavy foot and some high RPM shifting. Oddly enough, the only time it's ever showed me that it had enough was when it was in stop & go traffic for about half an hour waiting to get into a car show. Once I pulled in and parked it proceeded to puke it's guts out of the front dust cover. I had it towed home (only because I wasn't sure what had puked and I didn't want to chance it), added some tranny fluid after I discovered that the tranny was the culprit and it was like it never happened. Michael Stanford (San Marcos, TX) 1963 1/2 Ford Galaxie 500XL - 390 / Cruise-O-Matic (Project of ten years and going) 2004 Ford Ranger Edge - 2wd truck that gets treated like it's 4wd 2011 Jayco Jay Flight 22FB (Home sweet home!)

Post Aug 02, 2011 #13 2011-08-02T00:32+00:00

I thought that a 289 full-size from '67 would have a C4, not a Cruiso. I have a 'small case' cruiso that came stock in my 352-powered galaxie. With a stock rebuild and a modified valve body by Jay Broader it works pretty well. I still really dislike not being able to select between 1st and 2nd when manually shifting, but I don't know of a way to convert the trans from 'green dot' pattern to 'select shift' pattern... [/img]

Post Aug 02, 2011 #14 2011-08-02T02:33+00:00

The FX, MX, Cruise-O-Matic and FMX trannys are considered (by Ford) to be "medium duty" transmissions, the C6 is heavy duty. In my experience, the cast iron trannys in all variations, including the FMX are actually fairly rugged designs and will withstand considerable abuse. They were never as popular as the C4 and C6 for performance use, probably due to weight and a somewhat lack of performance upgrades. Trans-Go did have a High Performance "Shift Kit" for the FMX, but it is no longer available. I tried to get the "Stage-2" shift kit for the 72 Mustang FMX I recently rebuilt, and thats when I found the kit has been discontinued. I was forced to use the "regular" "Shift Improvement Kit" as that one is still available. Not a bad kit, but the Stage-2 kit had some extra parts for hi-perf use. A regular Shift Improvement Kit is also available for the 67 and older Cruise-O-Matic. When I first started building trannys over 30 years ago... I didn't like the cast iron transmissions... now I find that they can actually perform quite well, and as said, they are fairly rugged. Not the easiest trans to successfully overhaul, and they can be a bit finicky at times, and they do need more care on assembly compared to say, a C6. But all in all, If I had a car with one of the cast iron trannys, and I wanted to keep it more-or-less original, I would not be afraid to use the cast iron trans for street performance use. OTOH.... if all out performance is desired, no concern of originality, or even just to upgrade to a more "modern" trans, the C6 would be my choice. My 66 FE Galaxie came with the Green Dot C6 and I changed the valve body to the Selectshift, also installed E4OD wider ratio planetary gear set. (gear set change is major work for a minor change/improvement in ratios, not worth the trouble and expense on a street car, unless you are a trans guy and have access to the parts and can also do some minor machining) I also modified the console shift quadrant to show D-2-1 and modified/welded the shifter detent plate so there is a positive stop for the "D" position.   Edit; On the issue of your trans puking oil out the front (I assume it puked the oil out), Ford uses a front seal that, when it gets hot/overheated can do just that... puke out about 2-3 quarts of oil and then the leak stops... trans cools off, refill with oil and all seems fine... The issue is the seal material and the type of trans oil used. Even to this day, the material that Ford specs for the front seal on many of their trannys can cause that to happen, esp after a long hot drive on the hi-way. Stop for gas and the oil pukes out. Refill and carry on, no apparent other problem. The issue is the silicone rubber Ford uses for the front seal, combined with using trans oil OTHER THAN what Ford specifies. See, Ford spec oil uses an additive package that has a *small* amount of "seal sweller additives" where most other oils on the market use a much greater amount of seal swellers. This is not a problem when the seals are made with the newer "Vamac" or Viton type materials. But the "older" silicone seal don't like too much seal sweller additive, esp when they get hot. The seal gets soft, swells with the heat and leaks, then cools off and returns to "normal". Thus the mysterious "oil puke" and then it stops leaking. No apparent damage. I have seen this issue many times, and it is difficult to comprehend how it can leak so much, and then be fine. Difficult to explain to the customer. <img alt="wink.gif" src="/images/wink.gif" width="14" height="14"> Not all Ford present day trannys use silicone front seals, and for *some* trannys there is an aftermarket upgrade Viton seal avaiable. Most older Ford trannys are stuck with the silicone seal up to around mid-late '90's It used to be easy to ID the silicone seal, the material was orange in color, but now they make it in black and they look identical to the newer Viton or Vamac seals. Impossible to tell the difference just by looking. Some seals are still made in orange tho....

Post Aug 02, 2011 #15 2011-08-02T05:26+00:00

you never know what you might find...I have a C6 under my bench that I will build when this one gives me trouble or when I get really sick of the shift pattern. It's unlikely that I would bother to try and mod this trans any more. [/img]

Post Aug 04, 2011 #16 2011-08-04T00:27+00:00

The seal that was installed just before I put the 390 back in my Galaxie was orange so that likely was the problem. Plus, I've been using the cheap transmission fluid just to hold it over until I get the new tranny in so I doubt it liked that much. Thanks again for the valuable info. I'm likely to print up your responses now just to have for future reference. Michael Stanford (San Marcos, TX) 1963 1/2 Ford Galaxie 500XL - 390 / Cruise-O-Matic (Project of ten years and going) 2004 Ford Ranger Edge - 2wd truck that gets treated like it's 4wd 2011 Jayco Jay Flight 22FB (Home sweet home!)

Post Aug 06, 2011 #17 2011-08-06T23:09+00:00

Ahh, somebody that's worked on one. My 61 Cruis-O is slipping like a bugger. The C6 i've got would need rebuilding too. I can't seem to find pedals and clutch linkage for less than "R Code money" so i was thinking of rebuilding the Cruis-O myself but nobody I know has ever tried. Anything to be aware of before buying a rebuild kit?

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About a week ago my transmission started squealing when it is cold... seems fine once it warms up. But it seems like a warning sign of something or other. I thought that I'd start out by replacing the fluid and filter unit and see if that clears things up. Thing is I need to order a gasket and filter set, but I'm having a hell of a time figuring out exactly what tranny i've got... Seems that M&M's identification post is a touch short on pre 65 fords, as is the Napa parts book. Can some one help me to locate a part number that i can cross reference, or perhaps just tell me what was stock on a 1964 Galaxie Country Sedan w/ 4bbl 390 cruise-o-matic? Thanks, Bill  

Ford trannies They used 2 different 3 speed automatics in 64. C-4, used behind the 6's and small displacement V-8's and the FMX, which was used behind all the engines. The FMX is identifiable easily as the bellhousing and tailshaft housing are aluminum and the center section is iron. The nice thing about the FMX, is that the bellhousing can be swapped around to fit the engine application. Essentially, with the exception of valve body modifications, all FMX's are the same, regardless of the engine they were behind. That being said, there are also several different tailshaft housing lengths, to compensate for the different wheel bases of vehicles they were used in. The FMX, while not the hottest setup for racing, is a rock crusher tranny and will take more abuse than anything Ive ever seen. If you would like to get the 1,2, D shift instead of the 1, D2,D1 shift, all thats required is to use the valve body out of a 66 or later FMX.  

Max; are you saying an FMX rebuild kit will do a long case and medium case tranny? I have a ~'63 medium case one that probably needs rebuilt and am trying to decide what to buy. The vintage tranny parts house websites are pretty non-specific about FMX kits and that is probably why if they are interchangeable.  

FMX The only thing Ive ever seen that could be referred to long case or short case would be due to the length of the tailshaft. Other than that, all FMX trannies Ive ever been around were all the same as far as the center case is concerned. There were some minor changes in materials used inside them over the years, like a modification of the valve body, different vacuum shift modulaters. I would recommend going to a regular parts house for your tranny parts, rather than a vintage shop. One, it will probably be cheaper, and they can match up the exact parts for your application. There are some differences in clutch and band materials over the years as well. The nice thing about an FMX, is that you can take one out of a 73 Mustang with a 351 Cleveland, and by changing the bellhousing, bolt it up behind your 63 390 Galaxie. Everything will work, unless your tail shaft is longer. wich you can swap out as well, the shaft and tailshaft housing that is.  

This site talks a little about the 'small case' and 'medium case' Cruiseos. These guys talk about 'small case', 'medium case' and 'large case' Cruiseos. I guess going thru these sites will answer my own question!  

Cruisomatics Im going to take a look at those sites myself. It may well be that there are some cases Im not familiar with. Up til 58, Fords had a single range 3 speed automatic, called the Ford O Matic, then in 59, came out with a 2 sped automatic, which it made through 64. I dont know much about them, other than they were only used behind smaller engines, and was replaced by the C-4. That is a good article on the Cruisomatic and the FMX. I have never gotten that far into them. All Ive ever done was to swap out a bellhousing and put them behind an engine. I always used the torque converter that came with the case, and play with a valve body or two. The only thing Ive messed with were from about 65 on up.  

A little history, maybe some one can add to it I started working for Ford in 1979, in the old Transmission and Chassis Division. At the time I was working mostly on the just-launched AOD transmission and the soon to be launched and now defunct ATX, but I had a lot of involvement with all the transmission plants at one time or another from 1979 to 1986. In the process of trying to get a new transmission approved (AOD II, never saw the light of day) I had to do a little history write up on the Fairfax (Cincinnati area) transmission plant. This plant closed due to non-approval of the program as the FMX gradually died. In Ford powertrain strategy of the time (and to some degree now), the most desirable engines and trannies get put in the hottest selling vehicles. The old stuff gets put in the price-point vehicles. They call this "mix management". The FMX at that time was the old stuff -- AOD went in the good cars, C6's in the big trucks, C4s in the small and mid-size, until they ran out of capacity, FMX's filled the gaps. I was told at the time that the FMX was a compromise design to replace both the old Fairfax (FX) and an old Livonia (MX) transmission, when the MX had to be eliminated from Livonia to make room for the C6. I am guessing that both the FX and MX were different variations of Cruise-O-Matic. Maybe some old Ford guy will see this and add on.... By the way, the AOD took some of its design inspiration from the FMX, which was known as durable but heavy.  

With cast iron cruise-O trannys.. there were 3 sizes... small , medium and large case.... duh , LOL the large case was used in only the large cars like Lincolns , etc. Many of the large case crusie-O's also had an odd ball output shaft & yoke set... I am sure stu can better explain that setup Look at these crusie-o trannys for a pan with the filler tube threaded in it.. FMX has a filler tube that goes into the cast iron case of the tranny. The C-4 is an ALL aluminum case , tail housing & bell type tranny  

Crosley; are parts interchangeable between FMX sizes or are they all different inside?  

FMX trans As I said previously, the experience Ive had with FMX's, has been limited to swapping bellhousings to make the fit behind a particular engine, and doing some valve body swapping. It may be that the cases come in different sizes, but they all worked, and I never did any measuring out side of grunting a lot when lifting them. To my knowledge, there was only one FMX trans made but with some minor internal differences. The only thing I ever saw different was in relation to the tail shaft or the bellhousing, or valve body. The valve bodies all looked alike to me, the differences being on the inside. The last swap I did was in 84, with a 71 Ford pickup FMX into a 78 LTD. The truck had a 390 and the LTD had a 351 W. In fact I have two sitting in my garage right now; know anyone looking for some?  

[email][email protected][/email] said: Crosley; are parts interchangeable between FMX sizes or are they all different inside? Click to expand...

FMX Neither do I. The only trans I remember having a rear pump was the single range 3 speed Fordomatic.  

A 1964 with a 390 engine will have the medium size Cruise O Matic transmission. This is the one that morphed into the FMX. Not much will bolt into a Cruise O Matic from an FMX. The COM has a rear pump while the FMX does not. Some internals are the same but not many. Then there's the big mother. Which is all by itself. Just about everything is different. As Crosley mentioned they do have a weird output shaft/yoke set up. Instead of 20 - 30 splines there are 2 or 3. The size of the yoke would put a horse to shame.  

That's all really confusing! I'll stick with my Dual Range Hydramatics, Powerglides and 2004Rs. I do need to do a Cruise-O for the Mysterion though. The one I have came from a '63 Galaxie and looks identical to the ones Ed Roth used so I guess I need to check for oil filter shape and rear pump situation to figure out what it really is. Case measures out as a 'medium'.  

That would be the Dual Range Cruise O Matic. Rear pump. PRND2D1L. D2 has two gears, 2nd.&3rd. D1 has all three.  

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Cruise-O-Matic, troubles with th medium case MX

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Hello, I´ve got a 64 Thunderbird with a 390FE and a Cruise O Matic. I rebuild the Transmission with a rebuild kit from TBird HQ. I put the transmission back into the car, filled it with oil. I used B&M Trick Shift. I followed the T-Bird shop manual about the filling procedure. I had the car on a lift and had it running in D and R. When the Dip Stick showed "Full" and there was no strange noise I started a test drive. Everything worked find. The car accelerated smooth. But when I first reached about 50 mph it started to make a strange rattling noise. I actually stopped the engine to prevent damage. It was too late. When I took of the torque converter I saw that the part of the converter that drives the front pump was broken. I removed the front pump and had to see that the gears of the pump are broken too. Now I need the gears for the front pump and maybe a Torque Converter. Now the torque converter is at the local machine shop. They will weld on and remachine the surface. But I need the pump gears. Does anyone know if the pump gears from the FMX will fit my 64 Medium Case? And does a FMX torque converter fit my transmission?  

WOW! That's a LOT of breakage, are you sure the flywheel holes were centered where you bolted it up?  

Sounds like the torque convertor was not twisted all the way in. Was there free play after bolting it to the flexplate? Only source of hard parts I know of- Broader Performance Home Page  

The tranny will NOT bolt up flush if the Convertor is NOT fully seated, or am I wrong?  

Yes it will if you run the bolts down, but the convertor is pressing on the flexplate and that tension will lead to front pump damage. When assembled correctly, there will be play in the convertor and pump. The crank snout will also put pressure on the conv. and again press the pump.  

No, I made a stupid misstake when I assembled the front pump. I put in the inner gear upside down. DAMN. But I need to know if the FMX gears fit the MX front pump?  

T-Bird64 said: But I need to know if the FMX gears fit the MX front pump? Click to expand...

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