How to: 4r70w swap

decipha

Registered User
here's the write up that I've been asked to make for my 4r70w swap in my 91 titanium, this may not pertain to the 89-91 GURE and GSALC equipped ecu's as their pin out is probably different, you'll have to cross reference the differences between them and the later model ecu's
heres the full pin out for the 91+ ecu's for reference http://eectuning.org/forums/viewtopic.php?f=1&t=17040

here's the wires that need to be ran to the ecu, i hit the junkyard and cut off an ecu connector to use the pins, the pins unclip using a pick after removing the red retaining tab,its pretty basic, you'll know exactly what im talking about when you see it, i simply removed the pin from my junkyard connector and snapped them into my connector so i had something to tap in to

the 4r70w transmission harness pins changed slightly in 98, use this as reference for your specific trans

4R70W_harness.gif


the 4r70w under went some improvements in 98 making it stronger and more reliable, best bet is to source a 98+ trans, only the v6 engine and the 5.0 engine (explorer and mountaineer) have the correct 4r70w case with the sbf bellhousing, the 4.6L 4r70w excluding some unique pre94's have the modular bellhousing and WILL NOT WORK ON A SUPERCOUPE without a bellhousing or a case swap which is not really all the feasible since the correct trans could be had in the first place making life much easier

in 95 henry changed the tcc solenoid from 1 ohm to 10 ohms, the 95 vic town car and marquis were the only 3 that changed to 10 ohm in 95, all else officially changed in 96, you'll need a 1 ohm tcc from a pre95 transmission

i used a tcc from a 93 mark8, i used dikes and cut the connector off the tcc so i could retain the newer style board inside the trans rather than having wires dangle inside it, removed a couple bolts swapped it out and i was good to go

ecu pin #/ where it needs to be ran to
2 brake switch
5 transmission-oss
30 trans range MLPS, already ran to the trans stock
38 transmission-epc
41 transmission-tcs o/d cancel 12v input
46 sig return
49 transmission-TOT/TFT
51 transmission-sol1
52 transmission-sol2
53 transmission-tcc
55 transmission-tcil

the ecu unlocks the converter when you hit the brake thus pin2
pin30 is already ran to the stock aod/m5r2 trans, its part of the neutral start circuit, i tapped into it at the stock transmission harness under the car

pin41 i ran to my 97 cougar shifter that i scored at the yard, i wired it to the monetary o/d cancel switch and used a 12v source that was already at the center console for the console light, my o/d cancel switch now functions like stock

if you have a 91-93 sc you'll need to move pin 53 to 55, this is the upshift lamp module wire, doing this turns the upshift lamp on when you disable o/d and it'll also flash if a trans fault is detected, i also removed that stupid chime module as the upshift lamp being on will make it beep constantly when o/d is disabled, to each their own

pin46 is signal return, you'll need to tap into the wire at the ecu

the mlps changed as well over the years, you'll need a pre 98

the driveshaft between the aod and the 4r70w is different in length as well as yoke diameter, the 4r70w has the same tooth count on the yoke but its thicker and stronger than the weaker aod yoke, using an aod yoke in a 4r70w will leak at the tailshaft, unless you swap the tailshaft, the 4r70w and the aod tailshafts are direct swap outs, just unbolt and bolt the other back up, doing so you can use an aod yoke on a 4r70w

best bet is to snag the driveshaft from a 94-95 supercoupe and not have to worry about any fitment issues, i had to go the mark8 1 piece route :p keep in mind by going that route i had to get it shortened, for those that don't have a full machine shop at their leisure, expect to pay $75+ to get it cut welded and balanced

I gathered:
$35 w4h0 ecu from 95 mustang gt auto (i highly recommend the 94-95 sc auto ecu)
$150 2001 v6 mustang 4r70w with wiring connector and converter
$13 one piece aluminum d/s from 93 mark8 at the yard
$1 mlps and connector from 97 cougar, tcc from 93 mark8, ecu connector for pins
$12 new filter
$39 12qts mercon-v
$20 4r70w shifter w/ o/d cancel button from 97 cougar
$80 B&M bar and plate trans cooler
spare wire, solder and iron, electrical tape, rubber trans hose, and heat shrink wrap protective looming i had laying around

for a grand total of $350 after it was all said and done :lol: that's the whole she-bang for cheaper than you can even buy a baumannator and it works 1000x better

now keep in mind the 94-95 sc comes stock equipped with 36# injectors and EDIS ignition (89-93 have external TFI "DIS" ignition), the 94-95 sc ecu does not support the "TFI" ignition types, so if you do not wish to swap to the better EDIS ignition setup you will HAVE TO use a 94-95 mustang ecu in your 89-93 supercoupe which will require a chip to correct a BUNCH of stuff, so unless you have 36# squirters and the EDIS setup to swap in at that time, you'll have to factor in the price of a chip, im sure theres lots of folks around here that can do this it for you, but if not, shoot me a PM or an email and I'll send you out a chip ~$100
decipha at efidynotuning dot com

i reused the aod cooler lines and spliced in my cooler after the trans fluid exited the radiator, i mounted the cooler up in front the condenser directly in line with the vent port in the front bumper :D


i choose to use the 94-95 mustang v8 ecu since I had it laying around, another option would be to swap to edis and use the 94-95 sc auto ecu

if anyone needs a stock "supercoupe" tune for a cbaza ecu (94-95 mustang v8 ecu) PM or email me and i'll send it your way

be sure you set the mlps correctly, put the shifter in neutral and rotate the mlps until it lines up with the neutral mark then tighten it down, i then put the shifter in drive and set the transmission lever in drive and tightening the adjustment nuts to prevent being in between gear selections while cruising (which will damage a transmission). i used a 97 cougar shifter cable bracket so everything bolted right up smoothly

so was it worth it? HELLL YEAHHH, their's absolutely nothing like having your transmission shift and lock up right when where and how you want it to, changing my shift point, pressure, and converter lockup is as easy as just pressing a few buttons on the laptop :)


im sure there's something i missed but thats the gist of it, this was really basic and not hard to do at all, I'd rate this swap 2 out of 5 wrenches as for difficulty rating, all in all if i had everything from the get go i'd probably been able to knock it out in ~6 hours or so

i think that about cover's it if i wasn't clear or if i forgot something don't hesitate to ask
 
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I just put a newer 2003 v6 mustang 4r70w in my 95 because I blew up the stocker a few weeks ago. Here is the pin out changes for those that are upgrading to the newer 98+ transmissions. The 98 transmissions have better internals so are more desireable, in late 2003 henry stopped putting the vss splines on the output shaft so ideally you don't want to get a 2004 or 2005 4r70w as they would require some additional effort to get the vehicle speed sensor to work

pin changes on transmission connector for a 94-95 supercoupe
using a 1998 to 2003 mustang v6 transmission

attachment.php


this is the order in which i did it to avoid confusion
pin 7 remove pin and cut wire
pin 1 - 7
pin 2 - 4
pin 8 remove pin and cut wire
pin 6 - 8
pin 9 - 2
pin 10 - 6




pin 7 and pin 8 were additional power wires that aren't needed in the newer transmission as they are bridged in the newer transmission board, also the tcc, oss, and mlps, from the original transmission will need to be swapped over to the newer transmission, for the tcc i cut off the connector so the two prongs would plug right up into the circuit board just as the newer type tcc does, the oss needs to be swapped because the connectors are different, the mlps needs to be swapped because the newer mlps's are digital and have many little switches inside, if you want to use the newer digital mlps you'll need to wire all the switches in parallel to pin30 nds circuit and wire a resistor to each switch to replicate the voltage range of the analog mlps, if anyone wants to go that route shoot me a PM and we can discuss voltage range as well as resistor values

in more news..

I removed the qh from my 91 titanium today and swapped it into my 95 purple supercoupe to see how the new transmission was working out, well the 91 tune RAN THE 95!!!!

the czaw0 (94-95 supercoupe) and the cbaza (94-95 mustang) ecu's CAN RUN THE SAME BINARY!!!! although i do not recommend it because it didn't seem to happy about it and the datalogging was going ape shiit but it did indeed appear to function almost correctly, some calculations were inaccurate though so i highly do not recommend
 

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Decipha, you’re alright in my book.

I'm sourcing a beefy transmission for my '95 and this will help.
 
For transmissions you can use any 99-02 v6 mustang transmission without changing anything except repin the harness, change the tcc solenoid and install the shift lever. Keep in mind the output shaft will change to 8 tooth instead of 7. This means your gears may play a huge factor in which choice you make. an 8 tooth output shaft is limited to 3.27 gears. You can run a dallas mustangs speedcal or a dakota digital unit from summit to correct it. I greatly prefer the 03-04 transmissions as they have better internal components however they have no teeth on the output shaft so you must tear it apart and swap your original over.

To me that means a good time to do some other important upgrades such as the spiral retainer on the intermediate one way, sonnax pressure regulator valve, modify the valvebody and install a high energy overdrive band. It doesn't hurt to lighten up reverse a little by going to the 1 groove (short) servo. You may also want to take parts from your original reverse clutch and put the 3 plate setup in.

As a side note if you do not want to change the tune to eliminate the 3-4 flare at light throttle then you can use your original yellow spring and the flare will be reduced or eliminated.
Alan

Note: 03 is a partial year as some may have output shaft teeth and others do not. The ones with hardened gears do not have teeth which is why they are the best to get if you plan on upgrading it anyway.
 
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you'll have to tear it down and rebuild it

from post #2


decipha said:
I just put a newer 2003 v6 mustang 4r70w in my 95 because I blew up the stocker a few weeks ago. Here is the pin out changes for those that are upgrading to the newer 98+ transmissions. The 98 transmissions have better internals so are more desireable, in late 2003 henry stopped putting the vss splines on the output shaft so ideally you don't want to get a 2004 or 2005 4r70w as they would require some additional effort to get the vehicle speed sensor to work
 
Rebuild is a harsh term. It is more like reassembled it takes about 2 hours.
Typical parts list and cost you can avoid some of these things so I listed their importance you can use the converter from the core trans with your stock flexplate but if you plan on racing I don't suggest doing that the 12 inch converters should never ever exceed about 5200 rpms. You will need to repin the harness or if you want you can completely swap over your old electronics but that is a big risk at their age. If you have not updated the range sensor I highly suggest that for everyone. the old style ones are not sealed and can get water inside them.
gasket set $50-required
filter $10-highly recommended
cast pan $150ish (working on getting a better price they just went through the roof)-optional
converter $375-highly recommended
flexplate $55-highly recommended
accumulator springs $42-highly recommended
rear output shaft seals $10-highly recommended
high energy overdrive band $15-highly recommended
extra direct friction,steel and machined pressure plate $40-optional
extra forward steels and friction $20-optional
pressure control solenoid $65-optional
lockup solenoid $27-highly recommended
pressure regulator valve kit $32-highly recommended
sonnax servo pin $17-highly recommended
spiral snap ring retainer $5-required
reverse servo $18-optional
direct accumulator piston $13-highly recommended
lube mod $95 (alloy line with stainless fittings subtract $20 for steel line)-highly recommended if 3.55 or numerically higher gearing
wider pump bushing $5-optional
300m stub shaft $165- rarely recommended only if exceeds 500rwhp
there are some other parts available for very high power but that is a whole different can of worms
labor is about $150 but can go up if the transmission is damaged, high mileage or for very high power levels. Parts could then increase as well and depends on who does it. I think I could put one together in my sleep so it doesn't take me very long, cleaning takes all the time.
Alan
 
Also note late transmissions use the 24 count oss sensor which requires transfer of the original output ring carrier.Not changing that can be fixed in the tune but will cause extremely early shifts if not corrected.
Alan
 
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keep in mind that wouldn't completely apply to the supercoupes as the 94-95 supercoupes use the vss on the tail shaft for vehicle speed and gauge cluster, its only on the newer ecu's 99+ that actually calculate vehicle speed by output shaft speed

on the supercoupe ecu's the output shaft speed is used to calculate converter speed ratio, tcc slip/lock, and corrected vehicle speed however with the oss signal being skewed the ecu may throw up the tcc failed flag and unlock the converter then resort to using the vss for shift speeds
 
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Yes it does apply when using any late trans that doesn't have the vss teeth, Just changing the shaft is not enough the output ring carrier also changed. If you decide to use the newer output ring carrier you can change it in the tune, with BE it is OSSPUL-#of holes for vehicle speed sensor. The newer output ring carrier is 24.
Alan
 
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As a side note if you do not want to change the tune to eliminate the 3-4 flare at light throttle then you can use your original yellow spring and the flare will be reduced or eliminated.
Alan

Alan, what would you change in BE on a W4D2 cal to correct this?

I put an '03 4R70w (swapped tailshaft and output ring carrier with '94) in my old '94 and it has that flare at 3-4 shift. I'm very familiar with the 4r70w, but a NOOBIE with BE and QH..

300m stub shaft $165- rarely recommended only if exceeds 500rwhp

I broke a stock '99 stub shaft at 350whp, getting on the highway on a cold winter day during a 2-3 shift. I wonder if it was a bad batch? Anyhow, replaced with a 300m shaft. The 300m shaft is a nice tight fit into the direct drum, I like it.

Jeramie
 
Yes it does apply when using any late trans that doesn't have the vss teeth, Just changing the shaft is not enough the output ring carrier also changed. If you decide to use the newer output ring carrier you can change it in the tune, with BE it is OSSPUL-#of holes for vehicle speed sensor. The newer output ring carrier is 24.
Alan

yes alan you are correct, the supercoupes do have calculated vehicle speed, they do not use the vehicle speed sensor unless the oss fails

decipha said:
its only on the newer ecu's 99+ that actually calculate vehicle speed by output shaft speed


what is this 3-4 flare that I hear of?

is that just another way of saying that it shifts into O/D too early?

if thats the case adjust the sealevel shift funtions
 
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what is this 3-4 flare that I hear of?

is that just another way of saying that it shifts into O/D too early?

if thats the case adjust the sealevel shift funtions

RPMs increase smoothly in 3rd up to the 4th gear shift, then they flare (jump up a bit more like the tranny's neutralized) before they drop to the proper speed for 4th gear.

Think of keeping WOT when speed shifting from 4th to 5th on a five speed.

RwP
 
The oss isn't used the same way but it is still used. They will shift very fast if the oss is not correct. Figure it any way you want but I have seen it first hand. Also note on any transmission if you exceed 3.27 gears and do not want to use a speed calibration device you have to dismantle it anyway. The modifications required are no where near what a rebuild entails. As noted in last post The 03/04 unit is the best choice by far. You are also much more likely to pick up a low mileage 03/04 as compared to earlier models. The flare is because the new od servo spring is firmer, it can be adjusted in the pcm.
Alan
 
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If you unplug it that is what you get, but with it plugged in and a 24 count oss the transmission hunts for gears, shifts early, downshifts back, upshifts, downshifts. They use the reference somewhere I haven't looked through the files to know but I learned by accident on a 95SC. I had to pay for the tune to be fixed to correct it, lessons learned that way are not easily forgotten. The OSS is also used to calculate driveshaft rpms for max speed on most everything. I never understood why they used a vss and an oss because both are essentially the same but they did.
Alan
 
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