Hear I am playing with transmissions again. This question has been asked before but I have yet to see a definitive answer. Is the transmission bolt pattern on the Powerstroke the same as it is on the 7.3 idi? I know the converter pattern is different but I am pretty sure those are interchangeable. This would be a swap from a psd to an idi so as far as the computer goes I should be fine, right? The local ford dealership tells me that they are different but the tech wouldn't say specifically in what way. Any info will be helpful.

 

If we are talking the 7.3 PSD, then you are correct.

Yup. IDIs use a 4 stud while the PSDs use a 6 stud.

Nope. Assuming the plug would connect in for you, the internal electrical differences would damage your PCM. You will need keep the solenoid body from the IDI version and swap it into the newer PSD transmission. That *should* allow it to work. The older ones have some extra resistors on a PC board that is attached to the solenoid body itself while later ones have those parts moved to the PCM. The quick connect may also be different across the PSD transition but not positive. Swapping the solenoid body will involve dropping the pan to gain access to the torx bolts that hold it in place.

Keep the older MLPS just in case you have to swap that over too.

He probably doesn't know or if he did, doesn't want to take heat for it.

Also, what year of IDI are you working with here? If its 1992 or newer, you are fine, if its 1991 or older (and 2wd) then you will have no way to run your speedometer. 92 and up eliminated the speedometer cable and takes all vehicle speed signals from the rear differential sensor.

The shift linkage is also different across the 1992 change over year. 1992 uses a thick cable to move the shift lever on the side of the transmission. Older versions use a system of actuating rods and bell crank instead. The shift lever on the side of the transmission is interchangeable, but again this involves removing the pan to get at the small roll pin that retains it. Pulling that pin can also be a pain.

 

I've been thinking about this too. I've gone through 2 E4ODs in 50k miles (hard service...), both times the TC dies & took the tranny with it.
Are the E4ODs for the 7.3PSDs stronger? I vaguely remember reading somewhere that they are, but I can't find where, or what the differences are. What about the torque converter? Is the PSD TC stronger than the IDI one? If so, is there any reason the IDI flex plate couldn't be drilled for the PSD TC pattern?

 

do you have a trans temp gauge,external cooler and or filter?
have you made sure the radiators trans warmer/cooler is free flowing and not plugged up?
how many miles were on these trans when you started?
were you experiencing any electrical problems along with poor/firm shifts,OD light blinking etc?
whats your average total weight?

 

Yeah, going through two E4OD's in 50K is a little odd, gotta be something else to it.

 

Thanks for all the strait answers. Is there an aftermarket pcm system that will simplify the switch process as well as provide better shift quality? The truck I'm working on is a 1991 and the tranny came out of a 1999. I can get the tranny pretty cheap so I can afford to throw a little money at it if it makes the job easier.

 

The usual scenario is the trans starts shifting firm & sending codes. Usual codes are excessive TC slippage, then the TC lets go...
The 1st one was in the truck when I got it. At that point, no temp guage, external cooler, or external filter. That one was replaced with a Jasper rebuilt. I got a temp guage, cooler, & filter then. That one died within the warranty period, and was replaced with another Jasper rebuilt.
That one died just after the warranty ran out, and was replaced with a Ford rebuilt. That one is still in the truck, with no problems yet...
The truck is heavy, 9600# empty. Wintertime, I plow & sand, usually with a couple tons of sand in it. Summer, I haul material, and tow about 10k# regularly, so it sees pretty severe use...

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This is the controller I used for mine:
Baumann Engineering's Baumannator TCS (Transmission Control System)

They are replacing it with this one:
The OptiShift Transmission Control System

I have no experience with their new "optishift" controller but if they are able to match the reliability of the older Baumannator TCS, I would be happy to recommend it. I've been running the TCS for several years and it never gave me any problems. Tech support was also good and they are very helpful with figuring out setup issues I had early on.

1995 and up E4ODs are stronger than the older ones but I'm not sure if there are any internal torque converter differences. My hunch would be yes, but I can't say for sure. My suggestion is to always get as good a converter as you can afford because as mentioned they can, and often do take the rest of the transmission with it. Unlike the converters on the older C6 transmission, the E4OD converter is considered a wear item due to internal clutch and moving parts.

1994 saw a ball bearing center support that replaced an older wear prone bushing. All rebuilds are supposed to have this regardless of original model year. 1995 saw the introduction of a higher volume pump that moves about 15% more fluid than older ones. Ford dealer rebuilds are all supposed to have this. 3 pinion planetary gears were replaced on most heavier build transmissions (Diesel/F250s) with 4 pinion setups in 1994 as well. 1998 saw the optional steel carrier planetaries on super duty versions. If yours is a 1999, its possible that it has those gears.

In fact there is a long list of other updates that s pan the years between 1991 and 1999 but those are some of the more significant ones.

Phy:

I have heard of people discussing the idea of redrilling an IDI flexplate to match a PSD style converter but I'm not sure if its been done (or documented). In theory, it should work if you can have the flexplate drilled properly.

 

You've been very helpful and I appreciate it. I'll look into those systems and hopefully get that thing on the road soon.

 

Hey Brant, any update?

 

Sure enough the tranny bolts up fine. That's the last time I call the ford dealership. I have yet to get a new controller. I had an original valve body from my year truck that worked well so I put that on until I sort out it's problems.

The guys that sold me the transmission had the torque converter blow up. They bought a new one and the the transmission slipped after it warmed up but was otherwise fine. (Clutches slipping?) That was the story anyway. So I will pull it apart and see what what the clutches look like. I'm still looking into designing a mechanical shift system for the e4od so I'm not rushing the project.

Any advice on what else can cause the slipping (caused by a ceased TC) I am open to ideas. I may do an entire rebuild but this was supposed to have been in good shape so If the problem is obvious than I prefer to keep the money in my pocket.

 

`97 was the last year for the E4OD so yours will be the 4R100 trans.

 

I would never consider a transmission with a blown torque converter to be in good shape. When the turbine and impeller blades fly apart, they send that metal debris through the transmission where they can cause all sorts of havoc. Often the valves can get even small metal filings that scratch the bores enough that they will not slide properly anymore. Any sort of internal mechanical failure can do this, and the torque converter isn't isolated from the rest of the lubrication system.

Seals can also be torn on the clutch apply pistons such that they leak fluid pressure. In both cases, the symptoms can be temperature sensitive since fluid is thicker when its cold and the transmission is more able to perform properly even with some leaks. However as it warms up, more fluid pressure is lost and you end up with a slippage problem. In more extreme cases, it can cause a no drive when hot senario.

Your idea of a mechanical shift E4OD (rename to M4OD?) will get a lot of attention, I suspect. It won't be easy but I'm sure many would be interested.

 

Thanks for the tips. I got it cheap enough that a full rebuild won't put me back to far. That makes two I have to rebuild. Practice makes perfect.

I have gone through the mechanical shift question on here and it may not be worth the trouble but I like messing around with stuff.

 

So let me get this straight. You successfully bolted up a Powerstroke 7.3 E4OD to a 7.3L IDI block? I thought this wasn't possible. What year was the transmission? What did you end up doing for a flexplate?

Thanks