BINGO! That is the S/N on the truck. Ok, great info and I love the way people help each other out here! I wonder if CAT just puts the max hp that engine configuration can do and detunes it to what the trucks require to do the job and still have ok fuel economy?Well the fist thing that comes up on SIS when you put in that BET02639 s/n is:
Product Configuration
735_ARTICULATED Truck
Serial Number: AWR00321
So if that is the S/N on the machine I'm thinking it is the original engine.