I'm sorry if this is the wrong place to post this and I feel like it's probably been answered but I am planning to do a transmission swap on my 1990 f250 I have acquired a 4r100 transmission for the swap and I've been reading that it should bolt right up and the electronics will work. But the pump orifice thing is confusing me would it work to swap the pump out of the E4od into the 4r100 to not have to go through the process of resizing the orifice on the pump. And also will I need to swap the solenoid pack from the E4od

 

You need to swap the pump, the converter, and the solenoid body.

What engine is in your truck, and what engine was the 4R100 mated to? Also, are both 4x4 or 4x2?

 

My truck is the 5.0l v8 and the truck the 4r100 came out of was also a 5.0l both 4x2

 

Then with the changes I listed above it will work.

The 4R100 will have two sensors on top of the trans. Your harness does not have a connection for them, but your PCM can't read them, either. Just leave them unplugged to fill the holes.

 

Mark, How does the factory stock EEC-IV ECU control the 4R100 converter if it is just an off off signal vs a PWM signal [for the 4R100]? You are probably the only person that I would trust with the right answer.

I have read that the main differences between the E4OD converter and a 4R100 converter is that the clutches are designed to slip more on the 4R100 than an E4OD. I don't trust everything I read as fact and I believe I have only read that in one place. I have also read [probably the same thread] that you can install a 4R100 converter in a E4OD but not the other way around.

Yes, I do know there are differences in the pump orifice.

 

Both the on/off and the PWM systems end up with the same thing at the converter. A pressure differential that locks the clutch.

The on/off turns on the solenoid and the pressure change to lock the clutch is controlled by the orifice. That orifice is 0.030" if I remember correctly. The PWM system has no orifice, the pressure from the PWM solenoid goes right to the clutch. The PCM controls the pressure change instead of an orifice.

The PWM system was designed to allow for continuous slip. That means that at cruise conditions the system was designed to have about 20 RPM slip. The other difference between on/off and PWM is that in the PWM system the converter clutch is grooved so that there is some oil flow across the clutch face when the converter is locked. Using a 4R100 converter in an E4OD could cause a pressure problem due to the grooving. I am not sure what would happen installing an E4OD converter in a 4R100. There won't be the flow across the clutch that was designed to be there, but on the other hand, the continuous slip that it was designed for does not happen.

The PWM system was piloted on the 4R70W transmission. I forget the model year, but they had A LOT of durability problems with the converter using continuous slip; The rest of us were told we were not to use continuous slip.

 

My expertise is Mercedes and they used the slipping converter theory from the get go starting in 96, I always thought having slipping clutches was not a good thing, but then again, I'm just a dumb mechanic. They have there reasons. Their reason was they did not want the client to feel the converter engage/disengage. We never had a problem, but then again, Mercedes do not tow 10k objects behind them either.

Thanks for the explanation, I am certain I speak for many people, it's appreciated since you really do not have spend your time laying down the facts.