Forum readers,
I'm stumped. My 2015 Chevy Tahoe went to the body shop for 3 weeks to get hail damage repaired and when I picked it up there was a loud ticking sound coming from the engine. I immediately suspected a collapsed lifter and possibly low oil pressure, so I began troubleshooting by checking the oil level. Someone had overfilled it by 2 quarts and drove it 20 miles while at the body shop! (They are saying that they didn't touch the engine during the body work, so it couldn't have been them...) In any case, it looks like the cause of the problem was oil aeration and subsequent loss of oil pressure to the lifters. I used the stethoscope with the engine running and it was clearly coming from the right side, #4 cylinder at the valve cover. I bought the lifter release tool last week because I was fairly certain it would be a collapsed lifter, but after pulling the intake manifold and both valve covers, I'm not seeing any sign of a collapsed lifter. Now I am not quite sure how to proceed. I guess I'll put the intake manifold back on and fire it up with the valve covers off and try to feel for the culprit, and then take dial indicator measurements - my problem appears similar to what our host had in this video, but I'm not clear on what ended up being wrong with this engine: https://www.youtube.com/watch?v=0YPPsYbffAA
Attached are videos of my engine running before I opened it up, and the right bank cranking with a hand trigger attached to the starter relay slot (learned that trick from you CPR, thanks!). Although the sound does not come from the left bank (driver side), I opened up that side too and cranked it but didn't see any issues.
Looking for some expert opinions on how to proceed. I didn't catch his name, but Crazed Performance Repair is the best in the business for these issues and the only one I trust right now. What should I do?
Engine running:
Right bank cranking with starter:
Thanks,
Denny Smith
Denny's Repair Service
Elkhorn, NE
Judging by the fact the rockers are all moving I think you are on the right track I need to get a dial indicator on it. Unfortunately you might have a messed up cam lobe. First though make sure you check for loose rockers on the bottom of all the cam lobes on that side. Just in case you might have a slightly bent push rod or something. Also, you might want to pull the push rods out and see if they are interfering with anything. Check for wear marks on the side of the pushrods. This isn't uncommon because the factory didn't give enough clearance for everyday wear. However, if that's what it was I would doubt it would happen within 20 miles. It would be something that would slowly get worse and worse over time.