One Way to Save a First Gen: A4LD to 5R55E Swap (Completed) | Ford Explorer Forums - Serious Explorations

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One Way to Save a First Gen: A4LD to 5R55E Swap (Completed)

NICE59FORDF100

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OBD-1 Kenobi
::EDIT 4-10-2011::

The transmission is in and working. Below is the discussion and theory behind this swap and the ideas preceding it.


::Update 6-7-2011::

Ive added the wiring diagram to post 104

The parts list is on Post 105


Well, if your friends with me on facebook, you probably already know about this. If your not friends with me on facebook, then you should, cause im that cool :p:....Yea, not really

Anyway, what this is all about is any of us that have a first gen knows the Achilles Heel of owning one.

Bad head design?
Well, besides that

Poor fuel efficency?
Ok, other than that..

Horrible squeaks, rattles, pops, and you have to pull the motor to change the oil pump because of inferior oil pan design???
Ok, maybe there are SEVERAL Achilles Heels to first gens, but I feel the biggest one is the dreaded "A4LD of doom...." (I added the Doom part...)

What this build thread will try and demostrate is my attempt to retrofit a 5R55E transmission from a 97 Explorer into my first gen without mechanical modifications...A bolt in scenerio if you will. While there are many alternatives to the A4LD delimma, such as the M5OD, rebuilt A4LD, 700R4, or the Frakentranny, I know nothing about transmission interals, ergo, rebuilding one is above my skill level. But what I do understand is Ford electrical systems. Besides, I do not want a manual, a rebuilt will eventually turn into same problem, and I can not bring myself to put GM parts in my Blue Bandit :cool:

So, after talking with Kris a bit, I came up with this hairbrained scheme. Will it work?? Probably not. Will something break and explode and Jason Statham will walk away from it all cool-like, not turning around?
stathamdeath3.jpg

Most likely. Will I spend all this time and effort and money for not? It can be assumed so. But in the very small, minor chance that this swap could work and be sound, then I want to share it with all of you fine folks here and maybe, just maybe, another viable solution can be had for these crackpot transmissions called A4LD.

So In other words, A4LD = BAD
Bad_a4ld.jpg


And 5R55E = Good
good_5r.jpg
 



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So, lets look at why this might work, and some theory behind it. Put on your thinking caps kids, it's time for school!

The 5R is pretty much just an updated version of the A4ld. Same case, same bell housing, same length, same mother-in-law. So the actual bolting it up and having it installed in a first gen is the easy part.

The similarities, however, pretty much stop there. It is HOW the transmission is controlled that is the bugger part. See, the A4ld is hydralically shifted except for the 3-4 shift and the TCC shift solonoids, which are grounded out by the EEC-IV computer. Three wires, that's it. The 5R is completely electronically controlled, having 6 shift solonoids internally (4 for the actual shifts, one for the TCC, and one for the EPC).

I won't go into why I am doing this swap, as we all have been there. Loosing overdrive, burning clutches, ect. So how can the 5R work in a first gen? Well, on the surface it wont. The EEC-IV has no ability to shift the 5R and never will. BUT..the EEC-V pcm can, which I'll get to in a bit..

Now lets compare the 4.0 OHV motor in a first gen between that of a 4.0 SOHC out of, lets say, a 97. When Ford engineers began designing the SOHC motor, they didnt start from a clean sheet of expensive white paper. They tore the OHV down to bare essentials, and began designing. While the blocks are in no way interchangable, they are similar is casting. So having said that, ford engineers pretty much used off the shelf components in the motor. And when i say off the shelf, i mean sensors as well. Both motors use pretty much the same values for sensors between each other. This is why its possible to run a SOHC motor in a first gen using the EEC-IV computer and harness. The SOHC does have one additional sensor, the Cam position sensor. But from my research, i believe this is irrelevant. Even though 93-94 OHV recieved the same sensor. But I digress..

Ok, so what does this all mean? Well in order to shift the 5R, the EEC-V uses the readings from engine sensor data to determine things like line pressure, what speed to shift at, when to downshift, ect ect. So, using arbitrary mathamatical properties we can deduce that..

EEC-IV Sensor Value X = EEC-V Sensor Value X

thus

EEC-V Sensor Value X ~ 5R Shfting

Ergo

EEC-IV Sensor Value X ~ 5R Shfting

Ok, so now that we know that an EEC-V PCM can read and interpret EEC-IV sensor data, we have a game plan to make this transmission work. But how? Well, there's the beauty and curse of this swap..

The First gen will be running two computers:eek:

Yep, I said it. My plan is this, and this is the technical part: The EEC-V PCM will be 'piggy-backed' off of the EEC-IV harness inside the cab. It will only recieve inputs from the engine (MAF, TPS, Tach, HO2S, Crank sensor, and a couple others) and will only be able to output to the 5R through an actual 5R harness. The EEC-V will have NO motor outputs connected. It will simply be ran in parallel with the harness and, being fed motor sensor data, then it will, in theory, shift the transmission accordingly. Will it have a lot of MILS? You bet your overdrive it will. BUT...and here's where I am stuck out now for this swap...I need to be able to feed the EEC-V enough data without it putting the 5R into the infamous 'limp mode'. If I can do that, this thing is golden.

So now that i gave fried your brain with techincal mumbo-jumbo, wanna see some pictures? Here, I'll save yea the grief :D

The first thing I started thinking about it is 'how am I going to wire this up?' Well, in all honestly, I hate splicing wires IN the truck. Limited room, limited slack, ect. So I decided to add on top of this completely stupid swap, I wanted to make it 'Plug-n-play' and completely reversible. SO I bought this:
165715_679228394131_5856304_n.jpg


What you are looking at is actually a Rotunda Monitor Adapter Harness, part number 007-00081 for EEC-IV harness. It's actually a ford tool designed to extend the connectors for the EEC-IV for use with breakout boxes and what not, so the tech isnt crunched over in a floor board with the test equipment. $50 bucks on ebay. Then I bought all this for $40 bucks off a guy parting out a 98 on craigslist:
168985_678089451581_1660056_n.jpg


These are assorted male/female connectors, am EEC-V PCM harness, some factory relay boxes and then of course, the 5R tranny harness. Now its just a simple matter of wiring everything together and running the harness in the truck. Again, 99% plug-n-play like this. I like that idea :D Oh, but then I also need a computer! Well, again, CL saves the day and I get this for $50 dollars:
180401_687664203701_4457252_n.jpg


This PCM is perfect: Out of a 97, SOHC automatic with four wheel drive. Again, PERFECT!! SO, where am I at in this swap? Well, I am still in the planning stages and research, but all I lack now to make this all work is an actual 5R transmission...but, crossing my fingers, I will know by next saturday (3-5-11) if I can get one. Once I get it, and a free weekend, I'll wire all this up, and install it in the truck (Blue Bandit) and we'll see what happens..

SO there you go. A completely insane and Russell-is-making-this-harder-than-he-should project. I welcome all thoughts, concerns, questions, angry mobs with pitchforks, et al. But please, be gentle...my ego is very very fragile :D
 






Russell knows my thoughts, objections and concerns over this plan, but since I can't talk him out of it, I will do my best to help him fail miserably...er, succeed in every possible way. :D
 






Russell, knows my thoughts, objections and concerns over this plan, but since I can't talk him out of it, I will do my best to help him fail miserably...er, succeed in every possible way. :D

Thanks Dan...LOL. At least i am 38% confident about this swap. Would like to get up to maybe 45% though...:p:
 






I definitely think you should run an obd-2 dash connector so that you can communicate with the pcm and wire up a small led for trans shifting.
 






Umm, why not just use a single later EEC-V, OBD2 computer, for a OHV/5R55E equipped vehicle (Like a '99, for example.), to control the engine and the trans. I would think it would be much easier to add/change of few sensors to the motor, to make the OBD2 stuff happy, then this electrical snakepit you have planned.
Further, with an OBD2 computer, you can use an Xcal3 and custom tuning, to "turn off" functions you don't need. (like the rear o2s that you don't have.) You can also get James to do some custom tuning of the transmission shift points/pressures.
 






Russell pointed out above that the SOHC PCM will run an OHV and visa versa so it is a negligible problem. I also told him about the tuning to shut off features. I think $$ is his main concern, since he has already saved money by using slave labor in his 59 build
 






Good luck lol, I hope you pull it off, I'm definetly subscribing to this thread.
 












I definitely think you should run an obd-2 dash connector so that you can communicate with the pcm and wire up a small led for trans shifting.

That is something I will add as well. I will need the OBD-2 DLC in order to pull tranny codes in the future. I will also have the O/D off switch and the O/D light hooked up as well somehow. The column shifter mechanism should remain intact as it is the shifter cable that will be swapped out in order to maintain proper gear selection, and the second gen gear selection indicator can be made to fit a first gen IP cluster with a bit of modding.

Umm, why not just use a single later EEC-V, OBD2 computer, for a OHV/5R55E equipped vehicle (Like a '99, for example.), to control the engine and the trans. I would think it would be much easier to add/change of few sensors to the motor, to make the OBD2 stuff happy, then this electrical snakepit you have planned.
Further, with an OBD2 computer, you can use an Xcal3 and custom tuning, to "turn off" functions you don't need. (like the rear o2s that you don't have.) You can also get James to do some custom tuning of the transmission shift points/pressures. .

Trust me, I thought about this idea. But in the current situation I am in, I decided against it. Heres why.

1) I can only use an early second gen PCM. 98+ had pats and without the coded key, transiver, and pats module, the computer would not engage the fuel injectors. In my case, this si fine, except I am not sure if Limp Mode would be activated as well.

2) converting the entire truck to OBD2 is a facinating idea, however, you would need a lot more of the harnesses and computer systems. The OBD2 system commuicates with other modules through the DLC and is called the multiplex communication network, using digital signals over wires for all the computers to be accessed through one port (The DLC) In short, in order to conver the entire truck to OBD2, a lot more wiring would have to be done to intergrate the OBD2 to the first gen harness OR a donor vehicle purchased and the ENTIRE harness set (All 5 harnesses in a second gen, A) Engine/tranny harness, B) Engine bay harness, C) Dash Harness, D)body harness, and E) frame harness) would have to be transfered over. With the above mentioned swap, ill only have to splice in about 25-35 wires for the EEC-V and simply plug the extention harness inbetween the EEC-IV computer and harness.

3) The calibration stuff is pretty cool, and if all else fails, I will have to have something done about the additional three HO2S that my 92 doesnt have. I'm hoping that the lack of those vaules simply throws a MIL in the OBD2 but doesnt alter the transmission shifting ability.

4) And dan is right, money is a factor here. I wish I had the time to do an OBD2 swap on Blue, but it's not ruled out. PLus I like trying thigs that haven't been done before. Folks said a message center couldnt work in a first gen too :p:

5) If this works, It'll be another way for first gens to be kept on the roads with minimal wiring, and all the research done. If it doesn't work, I'm out a hundred bucks and ill bite the bullet and get another A4LD lol.
 






whoo hoo :bounce: Following along here and maybe be able to throw in my .09 cent worth here :D
 






Definitely following this! You'll do just fine with the 5r.....i'm at 201k on my original one!
 






Im absolutely subscribing to this. :D
 






You mentioned that the EEC-IV can't run a 5R55E transmission. It runs a similar transmission in the 1995 Explorer (4R55E). You could get a 1995 PCM & wiring harness which doesn't require any splicing, then swap a few parts off of the 5R55E to make it think that the 5R55E is a 4R55E such as the range sensor, EPC & TCC solenoids. You won't have a 5 speed transmission, but it will be a much easier job. Another option is to swap a 5R55S in with a stand alone controller like James did.
 






im very intrigued by this
 






Ok, just a small update. I havent started on the wiring for this behemoth project yet, as I still need to find a suitable mounting location for the EEC-V in Blue, but I did happen to find this :D:thumbsup:

190495_689923575901_6576892_n.jpg


198352_691125028181_6621681_n.jpg


195975_692065678111_2741238_n.jpg


This is the 5R55E that will be making it's way into Blue. And just so happens that motor will be making it's way into Shade before too long! Woot Woot!! Due to recent circumstances, the motor swap will have to happen first, but directly after that, I think i should have this tranny in before too long. I'm also trying to tidy up my little 'Wiring Spreadsheet Of Destiny' that will assist me in this, and hopefully others as well.

So, first gen drivers, question...

Where do you think a good mounting location inside the cab of Blue I should mount the EEC-V? I am thinking I like where the EEC-IV resides now, in the passenger kick panel, and have no problem extending the harness for the EEC-V, just trying to think of where...

Thanks for reading and sticking with me on this, I hope this all works!!!
 






maybe where the factory amp is mounted?
 












maybe where the factory amp is mounted?

Thats an excellent thought! I do have the JBL in Blue though, I wonder if I could squeeze it in...

25223_613994503371_667219_n.jpg


(Just had a thought...Is it sad I already had a picture of this for reference that I just pulled from Facebook:rolleyes:)
 



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are you going to make a wiring diagram for others to see?
 






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