1998.5 24v Engine Computer(5spd,4x4)
 

I have a perfectly good working ecm out of my 1998.5 dodge cummins 5spd 4x4. only reason i removed was to replaced with a custom tuned unit.$200shipped OBO. Numbers on computer are as follows ESN:56514123 So:98994 Unit:5253 Part#3942336

What would the effects be it I put this ECU into my truck with an auto transmission?

idk for sure but i dont think it has the parameters to make the auto shift. but not for sure might ask around a bit to make sure tho.

if your needing one for and auto, i have one off my 99