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Aod To Fmx Swap?

  • Thread starter Thread starter Nathan Reible
  • Start date Start date Oct 14, 2012
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Nathan Reible

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#1
  • Oct 14, 2012
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I'm running an AOD right now but it's pretty tired. I recently found a rebuilt FMX with the bell housing and converter for $200. Is it worth it and what is required to swap it over?
 
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Nathan Reible

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#2
  • Oct 15, 2012
  • #2
I just talked to the guy who's selling it. He bought it from the guy who rebuilt it, he said he hasn't put it in his car yet but everything looks good. He decided to go with a C5 instead and has no plans for using it. He wants $160 for everything, I think that's a steal price. I'm not planning on doing a whole lot performance-wise to my Mustang for now so I think it will be fine. I'll just keep my AOD and have it rebuilt later with a TCI Pro kit for future power-adders.

Would swapping it over require any additional parts since it has a vacuum throttle valve? I could probably just run a vacuum hose from my intake to it and call it a day. Is there anything else I would have to do?
 

88LX5.Oh

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#3
  • Oct 15, 2012
  • #3
FMX is quite possibly the worst transmissions Ford ever made. If I had one I would scrap it out in a heart beat.
AOD > FMX
 

mikestang63

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#4
  • Oct 15, 2012
  • #4
Why on earth would you go from an already weak AOD that was based on an ever weaker FMX? I think they use the same 164 tooth plate and bellhousing. You may need to swap out the yoke on driveshaft and fab up a crossmember, then work out the shift linkage , tv cable. Most people go from the FMX to the AOD or AODE.
 

ratio411

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#5
  • Oct 17, 2012
  • #5
FMX isn't a 'bad' tranny, but it is:

HEAVY! (Cast iron!)
Old... (Designed in the mid-1950s)
Longer than an AOD/C4/T5... (So it will need a custom driveshaft)
Harder/expensive to work on... (NO performance parts available AT ALL.)
and, IIRC, the mount location is not compatible with a C4 family tranny. The tailshaft position for the FMX is between a C4 and C6, which would require custom work on the tranny crossmember.

No wonder the seller doesn't want it.
 

ratio411

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Oh, and the FMX uses a kick-down, or so called 'passing gear' linkage.
It is similar in theory to the TV cable on an AOD, but I doubt you would be able to get the cable to work properly.
You can run an FMX without the kick-down in operation, but it will always accellerate like a dog unless you manually shift.
 

gearheadboy

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#7
  • Oct 17, 2012
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FMX= cast iron and alot of it. They weigh a ton. They don't work too bad but the thing is a monster.
 
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Nathan Reible

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#8
  • Oct 17, 2012
  • #8
I decided to just pull my AOD and rebuild it, that way I can keep overdrive. I'll probably buy a TCI pro kit to rebuild it with, get a mild converter (2500-2800) and call it a day. Anyone have suggestions for the converter? A street/strip is all I'll need.
 

gearheadboy

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#9
  • Oct 17, 2012
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Nathan Reible said:
I decided to just pull my AOD and rebuild it, that way I can keep overdrive. I'll probably buy a TCI pro kit to rebuild it with, get a mild converter (2500-2800) and call it a day. Anyone have suggestions for the converter? A street/strip is all I'll need.
Click to expand...
AOD converters are expensive. I think a TCI one is about the cheapest decent one.
 
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Nathan Reible

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#10
  • Oct 17, 2012
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Gearheadboy, I see you're running a manual rack and pinion in your Capri, how is it? My rack and pinion has seen better days, I thought about installing a manual flaming river as they're pretty inexpensive ($300).
 

gearheadboy

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#11
  • Oct 17, 2012
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When I did mine they were crazy. Mine is a new factory Ford unit. I love it. Steering shaft needs changed too, figure that in.
 
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Nathan Reible

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#12
  • Oct 17, 2012
  • #12
Yeah
gearheadboy said:
AOD converters are expensive. I think a TCI one is about the cheapest decent one.
Click to expand...

Yeah I know, TCIs run about $350-$400. B&M makes them too, they run a bit less...TCI is probably what I'll go with though.
 
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Nathan Reible

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gearheadboy said:
When I did mine they were crazy. Mine is a new factory Ford unit. I love it. Steering shaft needs changed too, figure that in.
Click to expand...

Is the Ford unit less expensive than the flaming river? How much would I be looking at total?
 

gearheadboy

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#14
  • Oct 17, 2012
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I bought a NEW Ford one on Ebay. Got lucky. Cheap. Flaming rivers are cheaper now. At least on Ebay. However they may be knock offs but they are cheap.
 
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Nathan Reible

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#15
  • Oct 17, 2012
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Yeah I just looked at a Flaming River Deluxe installation kit. It comes with the rack and pinion, steering shaft, outer tie rod ends and bushings for $411. I think it would totally be worth it as I plan to take this car to the grave with me (lol).
 

gearheadboy

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  • Oct 17, 2012
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Ya thats not bad. Are you sure you want to delete P/S on a street car?
 
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Nathan Reible

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#17
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I had a 90 LX hatchback some time ago with manual steering...it wasn't that bad. Plus my wife would be less likely to ask me to drive it (lol).
 

jrichker

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#18
  • Oct 18, 2012
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Unless you are modifiying the engine to move the powerband up a few thousnd RPM, use the stock converter. A looser converter allows more slippage at low RPMs to allow the engine to get up into the RPM range where it starts to pull hard. With a stock engine you run out of power above 5200 RPM, so you want it to engage soon. That way, you don't waste the best part of the engine's power RPM range, the part where it pulls the hardest.
 
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Nathan Reible

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#19
  • Oct 18, 2012
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My motor has an aftermarket cam, the few times I've driven it it doesn't do very well until about 2500 rpms or so. Anything under that doesn't produce much power at all.
 

ratio411

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Oct 21, 2012
#20
  • Oct 21, 2012
  • #20
Nathan Reible said:
My motor has an aftermarket cam, the few times I've driven it it doesn't do very well until about 2500 rpms or so. Anything under that doesn't produce much power at all.
Click to expand...
Well, then you certainly need a loose stall converter.

What rear gears are you running?
That is your next issue if you are dealing with a cam that needs to spin up quickly to make power.
The stall will help, but if your gears are too high (low number), you can even operate out of your stall's range and burn up your tranny from the heat.
 
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