I have a 6.4 truck motor. Im not sure what size cam is in it. It would be very hard to check. I would need to take it apart and put checker pushrods in it and my shimmed lifters and Im not sure what the cam lift even is on the truck motors.

Honesty, Im at a complete loss. I wouldn't think you would have got 3 miles out of it.
2.015-.080-1.40=.535