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Discussion Starter · #1 ·
Looking to get more gears in the future. Installing a 390 and fmx 3 speed this month but I will want to convert to a 4 speed automatic. Anyone have any suggestions. Not a race car. Street driven. Im on a budget so no $5000 transmissions for me.
 

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Simplest overdrive option would probably be a Gear Vendors Overdrive unit. No changing the transmission, just a new drive shaft. There was some discussion on here recently about getting GV units out of old motorhomes, but I don't know if many old motorhomes used the FMX.
 

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Discussion Starter · #7 ·
Simplest overdrive option would probably be a Gear Vendors Overdrive unit. No changing the transmission, just a new drive shaft. There was some discussion on here recently about getting GV units out of old motorhomes, but I don't know if many old motorhomes used the FMX.
I would be willing to replace the transmission for whatever worked. 3 gears just are not enough for what I want to do with it. The interstate is 75 mph and I dont want to cruise at 5000 rpm ya know. I even considered what it might take to put a manual transmission in there. Is that possible?
 

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I would be willing to replace the transmission for whatever worked. 3 gears just are not enough for what I want to do with it. The interstate is 75 mph and I dont want to cruise at 5000 rpm ya know. I even considered what it might take to put a manual transmission in there. Is that possible?
manual transmission? something like a Tremec TKO 600, maybe.
all depends on your budget.
 

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I would be willing to replace the transmission for whatever worked. 3 gears just are not enough for what I want to do with it. The interstate is 75 mph and I dont want to cruise at 5000 rpm ya know. I even considered what it might take to put a manual transmission in there. Is that possible?

The manual would be the easier and probably cheaper if your a junk yard junkie. But that said even then you still need an O/D trans, A standard toploader 4 speed is not an O/D.... What rear gear are you running anyways? Sounds like they are pretty deep... What IS the actual RPM's @ 75mph?

As was stated either way isnt going to be dirt cheap whichever way you try to go....

One adaptor 'kit' NOT CHEAP but an option, and as far as I can tell about the only one doing them...

MRO.....
 

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Discussion Starter · #10 ·
The manual would be the easier and probably cheaper if your a junk yard junkie. But that said even then you still need an O/D trans, A standard toploader 4 speed is not an O/D.... What rear gear are you running anyways? Sounds like they are pretty deep... What IS the actual RPM's @ 75mph?

As was stated either way isnt going to be dirt cheap whichever way you try to go....

One adaptor 'kit' NOT CHEAP but an option, and as far as I can tell about the only one doing them...

MRO.....
Right because I dont need the granny gear. Hmm...I dont know exactly what my gear ratio is due to its frame restore in progress. I drove it home and it was at 55 mph at 3000 rpm on my 302. Where I live, every road out of town is 75 mph to 65 mph. I just dont want to run high rpm's everywhere I go. I have not taken it to 75 lol. The front end was shaking pretty bad on the old frame at 55. The new one will get a front end rebuild. That "one adaptor kit" link didnt work for me.
 

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The manual would be the easier and probably cheaper if your a junk yard junkie.
I'm not sure about this part-
Switching from an auto to a manual would be much more involved than just getting a O/D auto put in.

The junkyard isn't going to help- again, because Ford never made an O/D tranny (manual or auto) for the FE.

You're going to be stuck going aftermarket (or adapters), whichever way you go.
 

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I went through this recently and researched the options extensively. Here's pretty much what I found:

Bendtson's adapter to mount an AOD onto your FE motor will run about $900 and includes a special starter that you'll need. Of course you'll also need a suitable AOD and TV cable. A stock AOD may not be up to the job if you wail on it much.

AOD with bell housing cut off and FE housing adapted on. Uses a smaller than stock torque converter. Seems like that was going to be around 2600 with torque converter from Broader.

AODE/4R70W with adapted bell as above, plus Baumann optishift controller. This is a stronger transmission and also is not prone to damage from a misadjusted TV cable. I think it was going to be about 3600 including the controller and torque converter. Also from Broader.

Gear Vendor unit, new from Gear Vendors. They have a unit with the proper adapter for the cast iron MX tranny found in the old Galaxies. I think the brand new unit is around 2500 or 2600. I didn't dig too deeply into this because I wanted the lockup converter on my OD tranny.

Manual overdrive tranny. I ended up putting in a TKO 600 which was a pretty fair undertaking requiring a fair amount of fabrication work (I did the fabrication and installation myself) and cost me around $4500 including the stock clutch pedal and linkage pieces which took a while to track down. Also included with that price is a top of the line clutch, pressure plate, billet flywheel and scattershield so I've got top shelf brand-new parts throughout and a brutal strong transmission that I feel is worth it.

No doubt there are other options but these are the ones I found that seemed sensible to me. I believe all of these options require some driveshaft work.
 

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that's some really good info-

only one thing to add- over on the truck forums, some of the guys are installing Dodge NV4500 manual trannys. I have no idea if this would work in a car. Again, it requires a $$ adapter.

+1 on the bit about hard-to-locate parts...clutch pedal setups can be found, but are expensive. and the Z-bar...ouch.
 

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Discussion Starter · #14 ·
Yeah thanks for sharing all the info. Looks like gearvendors might be the most cost efficient option. I didnt understand the videos I watched. Im a truck driver lol so hang with me here. It looked like they were splitting every gear in the transmission if that makes sense. Like they had the transmission geared to use the over/underdrive unit. I will look into it some more but it seems like a transmission regearing might be in order as well which is probably pretty expensive.
 

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Yeah thanks for sharing all the info. Looks like gearvendors might be the most cost efficient option. I didnt understand the videos I watched. Im a truck driver lol so hang with me here. It looked like they were splitting every gear in the transmission if that makes sense. Like they had the transmission geared to use the over/underdrive unit. I will look into it some more but it seems like a transmission regearing might be in order as well which is probably pretty expensive.
Yes, they can split the gears like that and I talked to Gear Vendors about it. They don't have a setup that will automatically split the gears so you would have to do that manually. Sounded like a bunch of nonsense to me, I don't know how you would ever time your manual shifts with the automatic ones! No matter the ratios in the FMX are fine, just let it handle 1-3 normally let the GV unit do the overdriven 4th gear.
 

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WOW 3k at 55? pretty deep gear in the rear..... or a very short tire..... sounds like the 4.30-4.56 range.... Bet it has decent take off tho.... ;)
 

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Discussion Starter · #17 ·
WOW 3k at 55? pretty deep gear in the rear..... or a very short tire..... sounds like the 4.30-4.56 range.... Bet it has decent take off tho.... ;)
Once this 390 is in there, we will find out! Its going to be a local car only until I can get some more speed out of this thing. I am getting another rear end next week with my frame. I think he said something like it being a 3.0?? I cant wait! Yeah this rear axel needs a drag strip. Plus its a posi traction I think. A good builder.
 
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