C4 transmission question

skidmarks

Well-known member
Early C4 transmission. Can you swap them out from a 24 spline to the later 26 spline by changing the entire front pump unit? Or is the case different?
 
No. At the least you also need the 26 spline direct drum. And as I remember there are other differences. However....., I don't remember the details as I did this about 25 years ago. I do remember it turned into a real can of worms!
Also, There is a pan fill case (dipstick tube threads into pan) and a case fill case (dipstick tube slides into a hole in the case). Pan fill case uses the front pump bolts to attach the bellhousing, and the pan fill case uses separate bolts for the bellhousing.
 
I think the pan fill set up was designed for trucks. Ford beefed them up a bit in 1970 or so in order to use them with heavier applications like the Bronco & light duty pickups. I figure if a person wants the heavier duty 26/26 spline set up then just find one. They are out there. Time will be better spent on other things rather than modifications of the old 24/24 types. They were strong enough to handle most applications they were intended for.


Those early ones were still five bolt bell housing pattern for the 64 & part of the 65 model year. The 6 bolt bell housings took over after that. Other than that, the transmissions were basically the same with smaller variations like the pump & pan set ups.
 
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Ok, so If I want to fit a C-4 behind my 292 1957 Y-block....any ideas, or concerns? Where can I source an adapter plate, etc? The 3-speed ford-o-matic with the sub-low is what I have now. The TV linkage is a problem for me.
 
I have seen 24/26 spline shafts available, is that for updating something or adapting a different converter?
 
Does the c-4 still need a kick-down lever? I'd like to get rid of that old bell-crank linkage on my 57???????
 
I would use a trans 1967 or newer, Shift pattern is Low, Second, Drive easier to down shift. The C4's that had the vent that looks like a mushroom are even better.
 
I would use a trans 1967 or newer, Shift pattern is Low, Second, Drive easier to down shift. The C4's that had the vent that looks like a mushroom are even better.


:confused: ... hmmpf ...


Now there is a good point I forgot about. SELECT-SHIFT over DUAL-RANGE!


THANX!
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rototwrench, but how will the AOD get the signal to lock up the converter? What about floor clearance? Seems like the motor is gonna have to come out to pull this off?
 
rototwrench, but how will the AOD get the signal to lock up the converter? What about floor clearance? Seems like the motor is gonna have to come out to pull this off?


AOD converter "lockup" is through the inner input shaft that is splined to the front half of the converter. There is no clutch, no solenoid, no electrical connections. The inner input shaft drives the overdrive planetary, so the converter is locked whenever the trans is in 4th gear. Simple!
The throttle linkage adjustment is critical. Get careless with it and the ****** is toast!
 
You might be thinking about the AODE electronic control transmission. 40 Deluxe has it right on the 1st Gen AOD. The computer controlled units like the AODE and the 4R70E did things with electronic computer control. This did away with the 40/60 dual drive set up but you have to have a computer & sensors to run them. The old AOD is all manual. If you update it with stronger input & wider reverse drum/band combo then they are pretty heavy duty units. I don't think the average Y-block could hurt one to easily. It has to have a TV cable just like the old FOM rod but they should be easy enough to adapt. The old TV rod might work but the pressures would likely be different at different throttle settings.
 
TV cable or kick down arm, they all have something to aid in control. The electronic ones use a drive train computer module to do it all. It's kind of take your pick but they all have something extra. My old el Camino has a T400 with electric kickdown so it has a switch on the gas pedal.
 
If TV is a problem, you have three basic choices;

1) Build an FOM/FMX Trans w Modulator Valve

2) Use later COM DUAL RANGE 1961/ )

3) C4 Conversion

4) AOD Conversion (still use TV Cable)
 
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Well my choces in order of preference are 1) try to work with the linkage issues have on the Ford-O-Matc 3 speed, 2) C-4 Thanks you all, this has been helpful.
 
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