I'm not sure that you have to switch to the lightning PCM if you want to run the 4R100 transmission. I'm pretty sure both transmissions use the same strategies and sensors. I would talk to a knowledgeable tuner. I know there are transmission type switches in the PCM as well as the ability to change the gear ratio of each transmission gear. I won't swear it can be done, but it's worth exploring. You may have to wire up some different harness connectors for the shifter switch.

 

Nope,,,not gonna happen. Been there ,done that.

Phil

 

ha i'll take your word for it then. well this kid says he can provide all the wiring harnesses for the engine bay and the trans (plus the pcm). it's actually a Harley pcm but shouldn't make a difference from what i am told. one thing i am wondering though is there any reason for me to grab his dash harness too just in case?

 

There is more wires in his dash harness then your trucks dash harness.
You need it or you can run the extra wires separately like my guy did so we didn't have to swap the dash harness.

Phil

 

Why? What problems did you encounter? I ran an E4OD off of AODE controls, so I've been there, done that too. Granted it was EEC-IV, but I don't think the strategies have changed that much.... well at least to adaptability.

 

Sorry but I cant give you a very technical answer but I can tell you that you Can NOT run a 4r100 off a 4r70w computer. We tried everything to get my 4r70 computer to run the 4r100 and it just dose not work.
The newer computers are transmission specific and you cant change the parameters from one to operate the other.
You can change them to run pretty much any engine combo but not the tranny.

Phil

 

Phil, do you recall which wires you had to run separately for your dash harness? this sounds like a total PITA...i would rather not R&R my whole dash if i don't have to. my swap truck is a 2000 XLT Extracab. i had an '02 Harley (sold in '09) but i don't know how the dash and body harness is different. would i be better off getting a pcm from a n/a 5.4 truck and flashing that instead of messing with the HD pcm?

 

If your going to use a 4r100, you need a 4r100 computer!
The dash harness is most likely the same between the supercharged and naturally aspirated trucks.
What we had to do was run 2 or 3 wires from the back of the computer to the plug on the 4r100 transmission wire-harness.
I'm pretty sure the dash harness plugs into the back of the computer and under the truck , the trans wire-harness plugs into the dash harness.
We just bypassed the dash and ran the wires separately from the computer to the plug on the trans wire-harness.
The wires we had to add, control the automatic shifting. It would not shift on it's own without them.

Phil

 

What is needed to put a 4r100 where a 4r70 was with 4wd?

 

hmmm...this sounds way too complicated. maybe i should buy a procharger kit for my 4.6 instead. i am just keeding! i am past the point of no return now, i have to make this swap my b!tch. okay i am picking up the L engine on sunday, i have a feeling i will have a lot of questions during this install so i will post a separate thread at that time...

 

that's like running a 4r75 off of a 4r70 ECM


and now that phil has beat the horse to death yet again, let it be stated taht you cannot run a 4r100 off of a 4r70 ECM

 

How do you figure that? Isn't the E4OD the predecessor to the 4R100? Sorry, if I've overstepped my bounds with my opinion.... which hasn't changed.

 

Yes, you can run a 4r75 with a 4r70 puter. It requires only a few re-pins in the trans harness.

 

One, I think you mis-read my point. But it's a moot issue. I checked with SCT and the strategies are different between 4R7XX and 4R100, as well as the PCMs, so you guys are right.

 

as long as we're all on the same page at the end