2018 6.2L, UPDATE: Lifter failure at 80k miles

[lbenson]

Hi Everyone.

I went out this evening and started my truck remotely in my parking ramp as I approached it. And then I start to hear this awful sound...

My guess is a lifter is starting to fail. It has given me 7-15 seconds of squeaky sound every cold start the past 6-8 weeks. This knocking or misfire is new as of today I think. It did quiet down a little bit when the engine warmed up but I can still hear it. Parked it after a few miles and going to let it cool back off and start it again later to see if it repeats itself.

Dang thing only has 79k miles. Arg.

If anyone has any thoughts LMK. Much appreciated.

Edit: let it sit for about 2.5 hrs in 25 degree weather. Not as loud as the video but more noticeable than when it was warm.

 

[Doubeleive]

sounds more like a misfire to me
either way you can narrow it down by pulling one plug wire at a time until the sound doesn't change

 

[wsteele]

It would be really helpful if you could do a recording with your phone near the engine with the hood open. Move around side to side and front to back on each side. Maybe someone will be able to give a definitive opinion. It is really easy to go down a blind alley when noises are the diagnostic input.

 

[lbenson]

It would be really helpful if you could do a recording with your phone near the engine with the hood open. Move around side to side and front to back on each side. Maybe someone will be able to give a definitive opinion. It is really easy to go down a blind alley when noises are the diagnostic input.

Good idea. I'll do it in the AM tomorrow when the engine is totally cold.

 

[lbenson]

Sent video to my service advisor. Said it sounds like it is knocking in the lower end of the engine, but since it quiets down after the engine warms up it could be an exhaust manifold leak.

 

[Geotrash]

Lifter. Frequency is too slow (half crank rotation speed) to be bottom-end. I agree that a video from the engine bay will confirm, but I have recently acquired a lot of experience with lifter failures.

Exhaust manifold leak is also possible, but I've had failed lifters get quieter as the engine warms as well, and to my ear that's a mechanical knock. If the squeaking noise you heard was also at the same frequency as the tapping you're hearing, my money shifts even further to a lifter as the root cause.

 

[TahoeLTZ2007]

I had a noise like that on my 07 5.3 l Tahoe.
it was exhaust manifold.

 

[avalonandl]

Piston Slap

 

[Tonyv__]

My van (6.0) made this noise on cold start then settled down. My exhaust had 2 broken bolts on both sides.

 

[THarber]

Check for broken exhaust manifold bolts.

Tim