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Discussion Starter #1 (Edited)
Please read this:

4R75W

"In 2003 Ford revised the 4R70W transmission with a stronger ring gear that had 24 lugs, as opposed to 6, for the output shaft sensor (OSS) to read off of, a new torque converter, a revised front pump assembly, and a vehicle speed sensor (VSS) that compliments the OSS to improve shift quality and efficiency. These improvements allowed the 4R75W to handle more power while being more efficient and economical. While not used on all 2003 model year vehicles, the 4R75W/E transmissions eventually replaced the 4R70W/E."

"Newer transmissions that are referred to as 4R70E or 4R75E have modifications that compliment Fords switching to throttle by wire. The PCM was given a more powerful microprocessor and Ford added a turbine speed sensor to the transmission. This allows the PCM to know the speed of the input shaft after the torque converter which is used in combination with crankshaft speed to detect the amount of slipping going on in the torque converter. This information provides PCM with the basis for fully electronic shift scheduling which limits "hunting" and fine-tunes shift speed and feel. It lets the PCM know what the torque will be in the next gear so it can choose the shift points based on the vehicle's projected performance in the next gear. Coupled with the electronic throttle strategy, the transmission computes the output torque required to maintain the vehicle speed, and chooses the correct gear and converter state accordingly."- Wikipedia

The 4r75E has been used in crown vics and in marauders etc. etc. These obviously have the same bell housing bolt setup as the 4r70w. The only problem with using one of these in our cars would be the computer/PCM since the vss, and oss can compensate for more T/Q "lock-up Lag" via PCM and possibly the tail shaft since its naturally larger in the crown vics.

Now its time for one simple question that I hope someone can enlighten me about; If hypothetically I was able to receive a PCM from one of the cars that featured the 4r75E/4r70E would it be possible to wire it in(re-spline) to our cars and then have the car tuned for this setup?.
 

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Double clutch?

A few things hinder the use of a 03+ 4r70w/4r70e/4r75w-e in earlier vehicles.

Lack of vss teeth on the output shaft (require teardown to replace output shaft)
oss output is 4x of what is expected (4r70e/4r75e) which can be compensated for

The tss was added so the pcm could vary lockup for a variety of reasons, including torque management and prolonging fluid life.
 

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Discussion Starter #3
Double clutch?

A few things hinder the use of a 03+ 4r70w/4r70e/4r75w-e in earlier vehicles.

Lack of vss teeth on the output shaft (require teardown to replace output shaft)
oss output is 4x of what is expected (4r70e/4r75e) which can be compensated for

The tss was added so the pcm could vary lockup for a variety of reasons, including torque management and prolonging fluid life.
My mistake about the double clutch part, that had no relevance to what I was originally talking about. So, this is possible to do with not to much to work on.(besides the output shaft part) Would you be able to program the stock PCM in an mn12 94'-95' year to adapt to the TSS?...Or is it only able to do with the 96'/97' PCM?
 

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I've not seen much better internally the main difference is the valve body
 

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My mistake about the double clutch part, that had no relevance to what I was originally talking about. So, this is possible to do with not to much to work on.(besides the output shaft part) Would you be able to program the stock PCM in an mn12 94'-95' year to adapt to the TSS?...Or is it only able to do with the 96'/97' PCM?
If by not much work you mean complete transmission teardown for an output shaft and possibly outer planetary ring gear and possible tail shaft housing swap depending on what it came out of, in conjunction with a repined or swapped internal transmission harness then yes it's "not much work".

I have a 4r75 Jerry Spec built transmission in mine. The only reason I didn't splurge on a few hard parts like a 300m stub shaft is because once I get to that power level that I'd break the 4r75 stuff I'd have bigger problems to deal with anyway like a de-splined forward hub or twisted direct drum. My gallery lists the build.
 

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Discussion Starter #6 (Edited)
If by not much work you mean complete transmission teardown for an output shaft and possibly outer planetary ring gear and possible tail shaft housing swap depending on what it came out of, in conjunction with a repined or swapped internal transmission harness then yes it's "not much work".

I have a 4r75 Jerry Spec built transmission in mine. The only reason I didn't splurge on a few hard parts like a 300m stub shaft is because once I get to that power level that I'd break the 4r75 stuff I'd have bigger problems to deal with anyway like a de-splined forward hub or twisted direct drum. My gallery lists the build.
Not much of that is INCREDIBLY hard to do if you have experience and the right tools. Now if you have no knowledge what so ever of the transmission and its components at all then yes this would be a nightmare. If im able to I'll check the pics out.
 

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To answer your eariler question. NO, you won't be able to program an MN12 PCM to run the stock 4R75W.
 

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Like everyone else mentioned, you can swap out the output shaft and the OSS ring gear, and the selector shaft, and you can run it in your car with the stock computer.
 

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Not much of that is INCREDIBLY hard to do if you have experience and the right tools. Now if you have no knowledge what so ever of the transmission and its components at all then yes this would be a nightmare. If im able to I'll check the pics out.
I had no knowledge whatsoever of transmissions and I can verify it is a nightmare:rolleyes:
 

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When you're rebuilding for your first time take lots of pictures and notes. I missed 1 bearing behind the direct clutch and smoked the clutch assembly. sunshell, and stub shaft. On a brighter note, I have a 4r75 in my tbird now thanks to a s#!^ton of guidance from Alan at dirtyog.
 
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