My '58 pickup has the 6-226 engine. When it warms up (run it for about 3-5 miles), it gets a really bad knock. It is the worst when the engine is running mid to high rpm. When the engine is cool, it goes away, or is very slight.

New Willys owner, so what I'm looking for is a couple of things:
-What could be causing the knock?
-Is there an easy fix?

The previous owner said that it was a wrist pin. I'm not sure, so I wanted to see if anyone else could weigh in. Yes, I am using Lucas Oil Stabilizer. It helped, but didn't get rid of the knock.

Any info is appreciated!