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So I've got an 08 Expedition with the 5.4L and the 6R transmission now for the wife.
This thing is over 5700 lbs and has 3.73 gears in the back.
How does it move so fast off the line?
First gear on the trans is 4.17 ratio, second is 2.34.

So some might call this a granny gear, but the way it bolts off the line I'm thinking a TBird with this unit in it could get some serious 60foot advantage at the track.

Anyone see anybody do a swap?

richardm
 

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WOT Junkie and avid corn burner
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I would think that would be the makings of some serious wheel spin off the line, especially with 3.73's.
 

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My F250 had a 4.76 1st gear and 4.10s, 0-5mph was instant. 5mph+ not so much, you'd have to shift by 15mph, so going too short may increase your ET because you've had to make 4 shifts instead of 2.
 

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I would think to run it in a tbird you'd have to do a pcm swap.... you'll need to control more shift solenoids.
 

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PostWhore, The AFDB is on a lil tight.
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6 speeds? go 4.10 in a bird. In the road tank expi 3.73 are better for mileage.

I cant Imagine how deep you gotta go to get it to work, ok maybe I can and thats why I I couldnt do it. I think if you have enough money and knowledge and do it at a shop it could be done. Does it even come close to bolting up? Does it fit the tunnel? I'm an inquiring mind
 

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Here's another thread from awhile back on the same thing. JL seemed to agree that it wouldn't be able to drive the solenoids. http://forums.tccoa.com/showthread.php?t=98331&highlight=6r75. I wish though. I think this would be a job for Cougar281 since he seems to not mind completely rewiring the car to swap different chassis computers in. Like his mach1 pcm.
 

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Baddest N/A NPI in Canada
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Of the research I have done. The 6R80 in the new Mustangs will fit in the tunnel of the MN12. You will need a to fabricate a new cross member mount for it to work as well as a new drive shaft. What is preventing me from moving forward with the swap is getting the transmission to work and to have a working odometer/speedometer. I am not finding a real simple solution to this.

One of the things that is really killing the enjoyment of driving the TBird is driving the Mustang. The 6R80 is far better than the 4R70W. I think if I was to put the same type of racing tires on my Mustang, a higher stall TC, 4.30's and a tune, that car will run high 11's and over 110 MPH in the 1/4 at the track I go to.

I think the only way my TBird is going to stay competitive with the new 5.0L Mustangs is to Supercharge it.
 

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You could wire it to run the first four gears from the eec, then use a toggle(or electronics) for the other two.

Would you really use 5th or 6th? Maybe on the street you could have a high/low range toggle. :)

Not having the 3-4 wot explosion of the 4r70w would make it worthwhile... :D
 

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Here's another thread from awhile back on the same thing. JL seemed to agree that it wouldn't be able to drive the solenoids. http://forums.tccoa.com/showthread.php?t=98331&highlight=6r75. I wish though. I think this would be a job for Cougar281 since he seems to not mind completely rewiring the car to swap different chassis computers in. Like his mach1 pcm.
Lol, I'm flattered! Before you even think about the electronic side of things, would the 6R's even fit in the transmission tunnel? As far as my rewiring, keep in mind that my 99+ Mustang PCM swap was less involved than what would be required to swap in oen of the newer PCMs. Not saying it's impossible to swap in an 05+ PCM, just more involved than what I have done. Unfortunately, since I don't really have any ambition to try and swap in a 6R transmission and am happy with what I've got set up now, I don't think you'll see me trying to swap in one of the newer PCMs. :)

Not having the 3-4 wot explosion of the 4r70w would make it worthwhile... :D
How the heck are you going to get a WOT 3-4 'explosion'? I had the same thought but calculated that a 3-4 WOT shift @ 6000 RPM would be something aroung 150MPH.... I kinda doubt that's a normal concern, so personally, I'm not worried about a WOT 3-4 shift on my 4R70W.
 

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Lol, I'm flattered! Before you even think about the electronic side of things, would the 6R's even fit in the transmission tunnel? As far as my rewiring, keep in mind that my 99+ Mustang PCM swap was less involved than what would be required to swap in oen of the newer PCMs. Not saying it's impossible to swap in an 05+ PCM, just more involved than what I have done. Unfortunately, since I don't really have any ambition to try and swap in a 6R transmission and am happy with what I've got set up now, I don't think you'll see me trying to swap in one of the newer PCMs. :)



How the heck are you going to get a WOT 3-4 'explosion'? I had the same thought but calculated that a 3-4 WOT shift @ 6000 RPM would be something aroung 150MPH.... I kinda doubt that's a normal concern, so personally, I'm not worried about a WOT 3-4 shift on my 4R70W.
I will say this again...

The 6R80 out of a 2011 Mustang GT WILL FIT in the tunnel of the MN12. You need to fabricate a new cross member mount and use a custom made driveshaft. Since I did not have a DS made, there is a possiblity of the DS rubbing in the tunnel as I did not explore that... The only reason I have not gone further with this swap in my car is that there is no real easy way to make this transmission work and to have a working speedometer/odometer.

On the WOT 3-4 shift. It really depends on the gear/tire combo. In 3rd gear with my car, it is doing 118 MPH @ 6500 RPM. Just as bad for the 4R70W as the 3-4 WOT upshift is the 4-2 downshift at WOT.
 

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I will say this again...

The 6R80 out of a 2011 Mustang GT WILL FIT in the tunnel of the MN12. You need to fabricate a new cross member mount and use a custom made driveshaft. Since I did not have a DS made, there is a possiblity of the DS rubbing in the tunnel as I did not explore that... The only reason I have not gone further with this swap in my car is that there is no real easy way to make this transmission work and to have a working speedometer/odometer.

On the WOT 3-4 shift. It really depends on the gear/tire combo. In 3rd gear with my car, it is doing 118 MPH @ 6500 RPM. Just as bad for the 4R70W as the 3-4 WOT upshift is the 4-2 downshift at WOT.
Sorry, I missed your post. Just for grins, I looked up some info on the 6R75 (I assume the 6R80 is similar) and it has an integrated TCM that sends a N/P signal back to the ECM/PCM and communicates with it via a high speed CAN network. Since the pre-05 PCM's don't support CAN and the electronics are part of the vavlebody (they call it a 'mechatronitic' TCM), I don't see any way it could be made to work other than a complete PCM swap. Electronically it's probably possible with time, some doner harnesses, and all the schematics, but then you'd have to figure out where you'd shove the PCM in the MN12. I'm not sure that there's room for it anywhere.

With the 3-4 shift, another thing that comes into play is the tuning. I have my shift points set up so it won't shift to 4th until I hit 55, and it won't shift to 4th if I'm even moderately into the throttle. It'll hold 3rd until I let up, then it'll shift into 4th.
 

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Sorry, I missed your post. Just for grins, I looked up some info on the 6R75 (I assume the 6R80 is similar) and it has an integrated TCM that sends a N/P signal back to the ECM/PCM and communicates with it via a high speed CAN network. Since the pre-05 PCM's don't support CAN and the electronics are part of the vavlebody (they call it a 'mechatronitic' TCM), I don't see any way it could be made to work other than a complete PCM swap. Electronically it's probably possible with time, some doner harnesses, and all the schematics, but then you'd have to figure out where you'd shove the PCM in the MN12. I'm not sure that there's room for it anywhere.

With the 3-4 shift, another thing that comes into play is the tuning. I have my shift points set up so it won't shift to 4th until I hit 55, and it won't shift to 4th if I'm even moderately into the throttle. It'll hold 3rd until I let up, then it'll shift into 4th.
Yes, you are going to need to do an EEC swap to control the transmission as well as swap in the gauge cluster from a newer Mustang to have a working Odometer/Speedometer. Lots of wiring fun...
 

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How the heck are you going to get a WOT 3-4 'explosion'? I had the same thought but calculated that a 3-4 WOT shift @ 6000 RPM would be something aroung 150MPH.... I kinda doubt that's a normal concern, so personally, I'm not worried about a WOT 3-4 shift on my 4R70W.
I missed this last week...

There are guys here that managed to break the intermediate shaft in two to three pieces doing a 3-4 wot shift; I'm hoping that was on the track. :)

Here's a pic of two pieces: (bottom pic)

http://forums.tccoa.com/showpost.php?p=1261861&postcount=19
 

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Someone will probably make a controller for the 6r80 later like the baumannator or whatever it is that also has speedometer outputs. If they dont....well they should!

My dads 09 f-150 has the 6r80 and it seems like a very good transmission, except for the wiring connector leaking atf which was fixed under warranty. Someone should also make an add on dipstick. It is super weak checking ATF from under the car while its running :(
 

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Someone will probably make a controller for the 6r80 later like the baumannator or whatever it is that also has speedometer outputs. If they dont....well they should!

My dads 09 f-150 has the 6r80 and it seems like a very good transmission, except for the wiring connector leaking atf which was fixed under warranty. Someone should also make an add on dipstick. It is super weak checking ATF from under the car while its running :(
There was supposed to be a an aftermarket controller out late last year. It is still not released and there is no time frame for it to be released.
 

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So your car is sitting with a 6r80 in it?
 

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So your car is sitting with a 6r80 in it?
Well yes and no. My Mustang does have a 6R80, my TBird has a 4R70W. My Bird was not the test fit guinea pig, it was a wrecked 95 4.6L car that I used to fit it. I really do not see me moving forward with the 6R80 swap. There is a lot involved with this swap and I do not really want to put the time in to do it. If this controller was to come out in the near future, I might reconsider it. I am more likely going to SC the car to get it where I want it.
 
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