Originally Posted by
madpogue
If you run an automatic PCM in a manual truck, it will probably perpetually throw the CE light with a bunch of tranny codes.
If you have an aftermarket chip, you can also get that re-flashed, and as long as you don't remove it, it will "trump" the PCM.
O contrar.... the auto pmc does not need any "inputs" from the auto tranny, in fact there are none in the E4OD. The only thing the auto PCM has that is different than the manual PCM is the smarts to shift the E4OD, which will no longer be there. So it will be trying to shift a non-existent transmission, but it won't even know it isn't there, because there are no additional sensors in the E4OD to feed back any info to the PCM. As I understand it the only difference in going from an auto PCM to a manual one is the way the fuel map looks. The fueling is slightly different, but should not affect driveability.
Obviously, you can't drop a manual PCM in an auto truck and expect it to work without re-flashing it to tell it to shift the E4OD, but going the other direction shouldn't really make any noticeable difference. I
f you're really worried about it have a chip with custom tunes burned and tell them what transmission you have.