LOUD Knocking LS2 05 GTO M6

**Revik** · 12-27-2020, 05:29 PM

Driving home from work on the expressway going around 80mph and heard a slight knocking noise which minutes later turned into a very loud knocking. Had the car shut off on me about 5 minutes after the sound started when I got off the throttle to get off at the exit. Removed the passenger side valve cover to check for any lifter issues and in the short inspection didn't notice anything different between the rockers. I did hear a small knocking noise about a week ago that only happened when I started from a dead stop and stopped once I got off the clutch completely.

Hoping for any issue not related to the bottom end but I feel like I will be disappointed.

Short video, notice how it slows/stops shortly after each rev and is not consistent.

**Scandrett** · 12-28-2020, 10:33 PM

Probably a rod.

**pajeff02** · 12-29-2020, 04:35 AM

Vids are so hard to tell anything by, but sounds too high pitched for a main or rod... definitely one sick engine.

Curious as to what you find.

**DoctorJ** · 01-12-2021, 10:25 AM

any updates with what happened op? the only thing i can add is a possible bolt break? i also read somewhere it could possibly be a flexplate issue. did you inspect more and see any condensation or anything loose, etc?

**desmond** · 01-18-2021, 06:13 PM

Hope that's not a major issue. My buddy got this incoming GTO M6 project and as per the current owner, it also has an occasional knocking issue. We'll take a closer at it after we finished installing the brake kit and black rhino wheels for suvs on the current Explorer project. Appreciate any update.

**RobertHuffman60** · 01-29-2021, 05:27 PM

Originally Posted by Revik

Driving home from work on the expressway going around 80mph and heard a slight knocking noise which minutes later turned into a very loud knocking. Had the car shut off on me about 5 minutes after the sound started when I got off the throttle to get off at the exit. Removed the passenger side valve cover to check for any lifter issues and in the short inspection didn't notice anything different between the rockers. I did hear a small knocking noise about a week ago that only happened when I started from a dead stop and stopped once I got off the clutch completely.

Hoping for any issue not related to the bottom end but I feel like I will be disappointed.

Short video, notice how it slows/stops shortly after each rev and is not consistent.

https://jeepequipment.com/

Sounds like a bad bearing.