so muck truck started knocking and i dont know whats going on with it. it had no loss of poer and no smoke. its sounds like its coming from the bottom end. i pulled the pan and the oil pum and pulled out all kinds of silicon and some metal shavings came out. i check to see if the flywheel was cracked but its not. i played with the rod bearings alittle bit and only have play from side to side. not up and down. when i drive it the nocking stop sparaticly. i dont know what it is. can any body give me some ideas

 

What do you mean by play from side to side? How much play?

 

Have you checked the crank journals for marring, scratches or anything that catches your fingertips?