i bought a 00 cummins with alot of k. engine is tired found an 02 with 120kms for dirt cheap. i heard the interchange is 02 only? what is different?

I'm not for certain, but I don't think there's much (if at all) difference in the 2000 and 2002 VP trucks.. Michael???

Just swap the ecms from the 00 to the 02 engine, IIRC the reason for 00 and up is the sensors are different there are different connectors on the AIT and or MAP sensor and the cranck sensor is different. from the older to newer. Just what I recall but don't quote me, you will have to look it over close.

01/02 don't have a crank sensor. If you do this swap you will need to swap your 00 crank shaft along with your front timing case and cam gear into the 02 motor.

The only thing to verify is the sensors. (Cam or Cam/Crank) I can never remember which year that crank sensors ended. But there was a change in the tone wheel on the cam when the crank sensor was obsoleted.W&F is right you want to swap the ECM over too.