Does new ecu have to be programmed?
 

I have a 97 b3500 5.9l. My mechanic told me I needed a new ecu. He said the best price he could get was $192 plus 40-50 dollars installation. I found an ecu on ebay for $60, it came from a 97 dodge ram 1500 with the 5.9. Would I have to have that ecu reprogrammed in order for it to work. Or should I just pay the $250 and have it done

Assuming both vehicles had the same type of trans, (manual, or auto) It would probably bolt right in and work. There is the possibility that the ABS, and Airbag systems would be annoyed though, and would want the PCM flashed with the correct vin for your vehicle. Not sure if that is an issue on the pre-98's though....

Welcome to DF! :D