L5P Duramax knock.

[Capt.Wackencracker]

Bought a new denali 2500hd duramax this week and heard a knocking noise immediately. 

Service advisor and diesel tech said it was normal. BS I say.

It's my 5th diesel. 3 duramax,  1 Cummins, 1 Cat.

Knocks at idle cold gets louder when warm. Gets quieter as rpm increases. 

My stethoscope gets the  loudest reading at egr area.

A lot of people on this website have also complained about this issue with their new (2020) trucks.

Please look at "Engine knock a 500 miles"  (that's "a" not "at") 500 miles.

On this website...gm-trucks.com

Hope you can help us all. Thanks in advance. 

[Colossus]

It is normal.  well that's what is being said to other new duramax owners complaining about the same thing.  Go over to duramaxforum.com and you'll see them crying about it over there too. 

[Jsdirt]

Just like GM told us burning a quart every 500 miles is normal. 

 

This company should do the world a favor and just go out of business already. Everyone will be better off, including most the employees that don't have deep 6-figure salaries ... 

 

I've never seen a company try to weasel its way out of every single warranty claim in my life. They're not even ashamed of it. What's even worse is they still have a loyal customer base!! 

[Havasubum]

I have always had luck calling GM Customer support.  They have been helpful for me.  Also, I have a friend whose Equinox is burning oil.  GM Customer Service took ownership of his problem and is currently helping.