this isn't GM but i thought this was the best place to put it. i bought a '72 peterbuilt cabover semi that has a cummins 350 in it and it had a bad knocking sound so i pulled the back head(1 of 3) and didn't see anything wrong and it looks like it was recently rebuilt so then i pulled the oil pan and found some broken pieces of what i think is a sleeve, i think they came from #3 cylinder because that piston is loose. so my question is do the cummins engines have a sleeve like a Detroit? if they do can the old one be pulled out and a new one be pressed in along with a new piston and rings on just that one cylinder or do i have to rebuild the whole thing? the truck probably wont get used allot but when it does it is usually pretty abusive.