Hello everyone,
I have a 1998 ford f150 extracab short bed 4x4 with a 5.4L. the transmission went out in it (came to find out it was teh forward clutch or somthing of that nature) and I thought it had a 4r10 in it. It comes to be a 4R70W in it. I have the 4r100 sitting there ( i got a great deal on a factory NEW 4r100 that I snatched it up. well now I am not sure what to do. I can A) either sell it for the 1500 bucks and get a remaufactured tranny or B) convert my truck to the 4r100. If I do B, which I would like to do I don't know what I would need to get to make it work as in shifter parts, computer and wiring. also driveline mods (as the 4r100 is four inches longer than the 4R70W. Has anyone done this conversion. any info would be appreciated.
Thanks,
Deric

 

I'd sell the 4r100 and build a good 4r70w for it. The engine computer and wiring harness will have to be changed. The driveshaft,cooler lines,flexplate,shift cable,misc brackets,and probably even the crossmember.
Alan

 

Well I found a deal on a used tranny 4r100 and the wiring and computer and he gave me the front driveline, cooler lines shifter for 4wd linkage, So I guess I will be doing the conversion. I will try to document the change for everyone interested in this. Wish me luck!

 

Good luck! You're sure going to need some good luck.

Getting it all mounted won't be all that difficult, but getting a computer that will run both the 5.4 and the 4R100 will be difficult! I hope you can get it to work.

 

It is easy. The truck I bought the wiring from had a 5.4L just like mine. the only difference I could see was that his was a long bed X-cab and mine was a short bed X-cab. Same year and same basic model. I am now just checking to see if I have to change all of the wiring and not just the tranny wiring.

 

There is a seperate wire harness for the tranny you should be fine and plug and play if the computer was on a 5.4 you got lucky. wish i'd have found a deal like that when i was doing the build up then i could put down some serious hp and torque without worry. keep us updated. was this out of a f250 or just one of those lucky f150 owners. are you sure it isn't a E40d??

 

I would like to say no for sure but I am not positive. THe 4r100 that I bought has two pickup sensors on the body one up by the torque converter and one down by the tailshaft. the tranny from the truck that I picked up doesn't have those. I have the tranny code and vin from the truck. Is there somwhere online that could decode the tranny code from the tag that is attached to it?

Other than that the transmissions look identical.

 

So you're trying to change a E4OD to a 4R100. That would be alot more simple. I'm not exactly sure what you would have to change ,but I know it is an upgrade to put the 4r100 parts in a E4OD. It would be worth tearing apart just to rob the parts and build your transmission with.
Alan

 

No actually my truck came with the 4r70w. I bought a factory new 4r100 thinking that is waht was in my truck. I now have found a guy with a wreck truck like mine so I go the wrining and misc. hard parts I need along with his tranny to put into my truck. I am not sure if it is a 4r100 or an e40d since it is out of a 1998 and they might have used both. but since it worked in his truck I am going to put it into mine. It doesn't make much sense to take apart a factory new tranny to take out the parts for the other tranny. I would probably just sell it and upgrade this one.

 

What is the tranny code letter from the door tag?

 

On my truck it is a U which I know now is the 4R70W i am not sure what is was on the truck that I got the tranny out of is though. but I do have the vin and the tranny tag info.