I have a 2003 f150 fx4 originally with 4r70w. I swapped out that for the 4r100 installed everything needed for the swap. Installed new computer with code (jld2) on it which is a 1998 f150 with a 5.4 and a 4r100. Now I got it started by turning off PATS but now the cluster doesn't read rpm, speedo, or miles on the truck. Also I went to drive it and it will not shift automatically only if I manually shift it from 1st into 2nd and when you shift it into drive from there it does nothing at all.

I unplugged the tranny harness and compared it to the plug where it goes and looks to me like a few of the pins are going into blank none used holes. Most pins are or seem to look correct. Only about 3-5 are being unused

If anyone has any suggestions please comment of pm me. Thank you.

 

You probably need to find a computer for a 99+, the only ones I know of that had a 4R100 are the 7700 GVW package, and even those went to a 4R70W in later years. You may also need the harness.

The 98 computer is for an E4OD - not EXACTLY the same as a 4R100.

 

That transmission harness plugs in to the solenoid pack. There are variances in the solenoid packs in that some use PWM and some do not - however, that SHOULD only affect the converter clutch.

How did you turn off PATS?

I don't know why your tach would be affected regardless of the transmission. Even if there were a speed sensor incompatibility, the odometer would at least initially show miles, then go to all dashes - trust me, I know this from the V10 swap.

 

I think I'm going to try to get a different computer and try it out. And I just asked the tuner to turn off pats but don't know the specifics on what he did