Hello,

I have done a bunch of research and have kinda hit a wall. I have read the bible by JMC on the 4.6 to 5.4 swap many times. great info there. I have a 98 f150 with a 4.6 couple weeks ago it toasted the motor. Ilooked around and couldnt find a reasonable replacement. I have a romeo and any 4.6 i found was a windsor, 5.4's i found didnt have torque converters or y pipes. I ended up buying a smashed up 99 expedition with a 5.4 with pats.

I called my local dealer, Dave marston motors, and their service told me they cannot reporgram pcms, nor could they disable the pats system.

after checking door tags, my 4.6 has a 4r70w, and the expediton coded E is an e40d or 4r100. obviously i need to run each pcm with its corresponding trans. I really wanted to stay with coil packs and wires which would make me use to 4.6 engine harness. Its rather a budget build, id rather save money on a custom reprogram and stick it into things like new main seal and new water pump stuff like that. if i need a custom tune then so be it.

My biggest hurdle right now is pcm, I would rather use the 5.4 pcm but it has pats, which I do have both keys, and all the components from the expedition. My biggest question is, is it possible to install a complete PATS system into a non pats vehicle?

I know most would say why bother, but if all i have to do is change a colum or better yet swap the pats module and reciever along with the cluster into my truck. I searched the web for a while now and cant find my answer, maybe just take an hour drive to a different dealer. thanks for the help

 

Not sure why you swap PCM's. With a swap like that, you use your existing PCM and trans. The 5four will even run with a 4six tune. Still, you'll want a custom tune for it to run correctly. You get that done at the closest speed-shop around you.

You may have to change the flexplate, but already have one if you do.

 

i would rather run the better trans, truck has a plow on it, that the previous owner plowed alot with. i know the 4.6pcm will run it, but being that i am keeping everything stock, maybe shorty headers for sound, i would think a custom tune would be overkill, the most i could see would be a mpg gain. It looks like any canned tune will only read off existing pcm data, for a baseline tune. i found a used canned tuner for a $125, which is a touch more than a dealer retune from what ive read. Id rather swap pcms, and get that tuner then have a dealer retune to stock 5.4.

Im out in the sticks, a custom tune shop would be 3 hours away minimum

 

No-way, not going to happen IMO. And, you'll have to tune it eventually. Not sure how long it will run that way = wrong.

Give it a try, -

Good Luck.

 

not sure how long it will run which way with a 5.4 pcm? which part do you feel is wrong?

 

A 5four w/a 4six tune. It's not going to run right. You said you don't want to tune.

If your serious about the 4R100, you'll probably need a Bauman controller for one.

Read this thread, -

https://www.f150online.com/forums/19...wap-notes.html

 

thanks for that link, you are right on the tranny swap, defiinetly not worth my time, i didnt realize how much that would take to swap. just as much as the engine!!
so without using the 4r100 trans then i wouldnt really need to use the 5.4 ecm except for the tune, i wounder how close the pinouts on the ecm are. but then again the 5.4 pcm is programmed for the 4r70w. which would require tune for that. sorry for the extra work reading your first posts informs better now after reading that link. anyways in all my reading i never came across someone doing what i am, so hopefully my questions will help somone else in the future.

New question, staying stock would you reccomend finding a dealer that actually knows what to do, or would it be worth it for a custom tune, ifso who would you recommend?
ive looked at many, most only list for 99+ but i assume if i call and tell them whats the deal they would help.

 

Been thinking about this. About using the 99 PCM. What's different beside PATs? The 98's have anti theft, not sure exactly where the differences are, but what differences are there with the cluster ? The 99 doesn't use a ECT sensor, but that easy to overcome. You'll want to use the expy rear end and D-shaft, IF the drive shaft will fit, it might, compare the wheel base.

 

Think I spoke too soon, it might be doable since you have the doner.

 

its completely doable, just not practical in my case, if the truck were better id go for it. if i were gonna go through all the work id pull the cab and go over it head to toe.

my 98 doesnt have pats, so the dash wiring might not work. the pcm talks to the cluster and the pats module and reciver, all of which i have. i to not have the rear ds from the expy, and the expy has coil with traction bars, vrs my leaf spring, it would definetly take some additional parts, and if the cab only had 80k on it and 1/4 the rust id go for it. but after getting your direct response i ahve concluded its not worth it. Ill go nuts on my next one...

 

Well, your still going to have to modify the ECT sensor, since the 99 doesn't use one. Might have to lengthen the IAC wire. Also you'll need a 5four tuner.

 

I'm not sure this will help much without using the 4R100, but the Super Duty 5.4 PCM doesn't have PATS so you could use one of those.