1995 ECM in the manual and automatic transmissions

[JulianGrives]

I'm currently researching engine swapping for my 95 Chevy. It originally had the 4.3L V6 with the 5-speed manual. I want to swap it with a 5.7L V8. I already know that it will bolt to the same transmission, but I'm looking to pull the 5.7 out of a junkyard (out of a 1994-95 to be exact) and I don't know if ECM is different depending on the transmission. I want to know if it would be ok to pull the 5.7 out of a truck with an automatic transmission, or if I have to find a 5.7 already mated with the manual transmission, then pull it and swap the ECM in my truck when the engine goes in.

 

[PlayingWithTBI]

I don't know if ECM is different depending on the transmission. I want to know if it would be ok to pull the 5.7 out of a truck with an automatic transmission, or if I have to find a 5.7 already mated with the manual transmission, then pull it and swap the ECM in my truck when the engine goes in.

Yes, the PCM for a manual trans has different controls for reducing RPM when you lift off the pedal, the engine coasts down to idle slower to make it easier shifting gears, etc. It'll probably have a shift light too. The PCM for an auto trans has switches for park/neutral, OD, and output for TCC lockup. So, either get a 5.7L out of a manual trans truck or, get a corresponding chip for it.

 

[tayto]

94/95 with manual trans still runs the 160 baud C3 ECM. you will need to burn a custom chip if you want to retain your original PCM