So I have a high pitch hiss/whine noise that only happens on a cold start after sitting all night. It doesn't seem to happen if I am plugged in overnight. Is this a normal 6.7 noise or something to be concerned about? It sounds like the noise coming from the exhaust or lower engine on the passenger side. The video below I am holding the phone under the passenger door.

Here is a video of the noise when it is 43* outside. The noise lasts for about a minute or two before it stops.

 

It almost sounds like the turbo spooling up after the initial start. But IMO it's hard to tell from a video.

 

 

Huh?, my truck sounds exactly like that when cold starting (not plugged in) I thought it was normal!! After about a minute to a minute and a half it sounds "normal"

 

turbo vanes closing to help warm up. normal

 

Maybe there is a problem, maybe there isn't. These new diesels are so quiet that we now hear other things that may have been normal years ago. I'm not saying one way or the other here, but it sure sounds like the turbo spooling up after a start. When in doubt, take it in and have it checked out. My 2003 Cummins made so many noises and that was how you knew it was running.

 

Sounds exactly like mine

 

Same with my 19'. Nothing to worry about.

 

Thanks for the responses. Its good to hear that it is a normal sound. I'm coming from a gas motor so these diesels make lots of new wonderful noises that I'm not accustomed too. I'm having the dealer look at it anyways while it is there at the end of next week to have a few other things addressed.

 

My 2018 6.7 sounds the same on cold starts as did my 2008 6.4.

 

Same noise at similar temps for mine, '17 PSD. I thought it was an air pump hissing/whistling helping out with the diesel emissions on cold start but it always goes away and doesn't do it on warmer mornings.

 

Same like mine. I went to dealer and started 3 on the lot. All of them do the same . Mechanic said it's normal

 

I believe that you may hear a change of tone at the exhaust when the vanes open or close.

 

 

Thanks for the reply's guys, thought it was normal for a cold morning start for the diesel. My 05 would do the same thing but much louder but would settle down when warmed up a bit.