2012 detroid locked up

[Hammerhead]

(02-14-2017 )sbtrucking Wrote:  cams and rolers look mint,
can I replace the crank an bearings only?or do I have to split the head and pull the pistons out?
Truck has little over 600k miles

Do you mean without pulling the motor out of the truck?
I wouldn't attempt it.

I would at the very least say you should pop the head off and remove that piston so you can confirm that rod isn't bent. It would suck badly to get it all put back together only to find out that the rod is bent and you now have to now go through all of that hassle again...and that's finding the bent rod from vibration, not creating a very large unevenly shaped inspection hole in your block and/or head.