Isuzu Repair: GMC W4500 with Isuzu Diesel Engine, gmc w4500, diesel engine

Question
I have a 2000 4 cyl 4 speed automatic GMC w4500 with an isuzu diesel engine in it that I purchased recently. How do I tell what size engine is in this truck. There was a sticker on top of the engine but is half missing. Can I tell by the serial #? serial # JBDC4B144Y7006576

Answer
Well if the serial number is clear and on the actual engine block then yes. Although since it was swapped the best thing to do would be to get in touch with the previuos owner to get any and all info you will need okay? I would start by taking it to NAPA and having them run it. They are pros and know whath they are doing.