push rod ?

Great. Which ones had holes? And why? Please don't say "Magnums", because that is not what the OP has.

In the land downunder, Australia, Chrysler used oil through pushods in all their small blocks. This was to improve reliability and reduce wear in the upper valve train. If I was the OP, I'd get some extra oil throughs and run them on all the lifters. It's a factory improvement to the valve train.