started hearing a knocking from the engine. stethoscope on the oilpan didn't lead me to think it was a rod. Still, i pulled the pan and didn't see any issues. could really hear it on the front side of the motor, so i pulled the timing chain cover. right side had some slack, but the slack would move to left after manually turning the crank. But yesterday, i noticed these marks on the chain guide. The crank chain doesn't feel loose, but something has to be doing this, right? i've ordered complete kit, so hopefully this will fix my problem. 2013 4.7 with 190k miles...
