1971 C-10 knocking sound and not reving past 3000 RPM

[BugzC10]

Originally Posted by aruss99

Ok, to check the lifter, can I just pull it out? Or is there more to it? Also, if the lifter is messed up, can I replace just that one? Or do I need to replace them all?

If you get lucky and it's just the lifter, it is my understanding you should replace all of the lifters. There's also a school of thought that you must put in a new cam along with the new lifters. Pull the rocker arm off the bad lifter and pull out the push rod to see if it is bent.