Is there a difference between a late 97 4r70w and a 98 4r70w trans? | Ford Explorer Forums - Serious Explorations

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Is there a difference between a late 97 4r70w and a 98 4r70w trans?


Elite Ranger
Elite Explorer
September 16, 2002
Reaction score
City, State
Virginia Beach, Va
Year, Model & Trim Level
00 4x4 Mounty
I am putting together everything I need for a v8 swap in a 01 ranger 4x4. I will be using a 97.5 parts truck and need a transmission. I have found a 98 trans and the interchange lists it as different. I do know the speedo is in the t-case in the 97.5. I would rather use the 98+ trans because they are better built. All I need to know if I can make it work.

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there may be differences in the wiring

there may be differences in the wiring

That is what I am thinking. The speed sensor for the t-case is not in the harness on the 98 truck so that might be the reason they list it different.

If you have both trannies to view, check the main case number on the thin aluminum plate which is attached to all of them. I cannot recall which is the 98+ case code desired, but I think I'd recognize it if you post it here. Look for something like "P8X" or a similar 3-4 letter code. There are many various items listed on the tag, only that I'm referring to is important.

The 98+ has one big improvement over older 4R's, and one fairly important change. You know about the mechanical diode in all 98+ models, but that's easy to buy and install in any model, back to the AOD's.

The case changed in 98 also(thus the requested tag code), before then the OD accumulator bore is a smaller size. The 98+ use a larger OD accumulator, and before then a sleeve is used with the accumulator IIRC.

The wiring did change for 99+, I think 98 is the same as 97 down. You can tell by the color of the case connector going into the trans. Is it white or black, are they the same color on your two examples? The wiring changed going through that connector in 99+ models, so either the harness wires have to be moved around, or that in trans harness has to be swapped(which is mated to unique connector shift solenoids(avoid changing that harness)).

Ok so I went ahead and picked up the trans. Its half off at our local pick n pull and I scored this trans with 134k on it for $84 so its worth a shot.

That "PKF" is what you have and want to see. There will be a black connector to the left of that and down I believe.