HELP!!! Motor knock!
I have a 2006 GMC sierra, 4 door, 4.8l, 2 wheel drive with 104,000 miles. Just recently after a 270 mile trip it developed a "knock" or tick in the motor. It was an all-of-the sudden noise, just went outside, cranked it up and there she went. The knock follows the rpms, it speeds up with the motor, but doesn't get louder and actually seems to go away when the rpms are around the 3000 range. I've always changed the oil between 3000 to 4000 miles and the truck has great oil pressure and runs as smooth as ever. Pulley noise has been eliminated as I've taken the belt off and cranked it up and it was still there. I've never driven the truck hard and have always taken good care of it. Any suggestions would be awesome. Thanks!