cold start noise on 6.6 gasser

[Colossus]

That's right.  It's NORMAL. 

[Carolina]

Mine has 1900 miles now and stopped doing it . Don’t know when

[Dunn]

i hear all kinds of strange noises all the time.....could give 2 ****** until something starts going haywire.....its got a warranty so if it ****s up its on them.....it drives absolutely perfect, so it can make all the noises it wants, lol

[M1ck3y]

On 1/26/2020 at 9:24 PM, CamGTP said:

Sounds exactly like the oil pump that is a common thing on the 5.3/6.2's.

 

It only happens on cold starts in the winter time for me. The variable oil pump is pumping itself back full of oil.

yup, my 17 6.2 and 2010 5.3 did that too. -15c or colder. I stopped using castrol and it seemed to disappear though.

[crash heap]

My brand new 21 makes this noise too. My wife's 04 yukon xl with the 5.3 makes it as well. Same exact scenario, once truck is warm it doesn't do it. The yukon has a lot of miles so I didn't think much about it. I preferred the way that the 6.0 sounded at idle as well. The 6.6 is kinda ticky. I like the truck a lot though

[L8T]

On 12/12/2020 at 5:48 AM, crash heap said:

My brand new 21 makes this noise too. .........I preferred the way that the 6.0 sounded at idle as well. The 6.6 is kinda ticky. I like the truck a lot though

Ya that’s due to the direct injection injectors. The higher pressure and engine design in general makes them noisier. 

[kdub]

On 2/16/2020 at 9:44 PM, KGray said:

 

Same for me...2020 Chevy 2500 HD 6.6L Vortec. I'll say the noise started around the first oil change and always the first/cold start of the day. I did some research and found GM's bulletin (see below). Very annoying to say the least!

https://static.nhtsa.gov/odi/tsbs/2020/MC-10176650-9999.pdf

 

 

Edited March 6, 2021 by kdub
updated bulletin to include the L8T motor