Whining noise when truck shifts into 4th and 5th gear?

[No F-bdy Bs]

Noticed this the other day. 

Brand new, as in 200 miles. 2025,6.6 gas. 

When accelerating normally from a stop, there is an audible whine when the truck shifts into 4th and 5th. Seems to go away after that. Not super loud, but noticeable. Sounds like something engaging. 

 

Thoughts? 

Edited January 25, 2025 by No F-bdy Bs

[BuckWallace]

Does it sound anything like the video in the first post in this thread? 

 

https://www.gm-trucks.com/forums/topic/264976-normal-l8t-noises/

[vucelick]

Do you have it in four wheel drive?

[No F-bdy Bs]

10 hours ago, BuckWallace said:

Does it sound anything like the video in the first post in this thread? 

 

https://www.gm-trucks.com/forums/topic/264976-normal-l8t-noises/

Yes, that sounds very much like what im hearing. 

 

Read through the thread. Did anything ever come to a conclusion? 

Normal operational noises, or something else? 

[No F-bdy Bs]

51 minutes ago, vucelick said:

Do you have it in four wheel drive?

No. 

[BuckWallace]

16 minutes ago, No F-bdy Bs said:

Yes, that sounds very much like what im hearing. 

 

Read through the thread. Did anything ever come to a conclusion? 

Normal operational noises, or something else? 

I never took it in for that, but enough people have said theirs does the same that I assumed it's just normal. It otherwise shifts fine, so I don't know...

Edited January 25, 2025 by BuckWallace

[No F-bdy Bs]

22 minutes ago, BuckWallace said:

I never took it in for that, but enough people have said theirs does the same that I assumed it's just normal. It otherwise shifts fine, so I don't know...

Copy that, thanks.

My dealer still owes me a bedliner, and I'll be ready for my first oil change so I'll probably mention it to them so there's  documentation, even if nothing comes of it just to hedge my bets. 

1 hour ago, vucelick said:

Do you have it in four wheel drive?

No. 

[BuckWallace]

2 minutes ago, No F-bdy Bs said:

Copy that, thanks.

My dealer still owes me a bedliner, and I'll be ready for my first oil change so I'll probably mention it to them so there's  documentation, even if nothing comes of it just to hedge my bets. 

No. 

Let us know what your dealer says. I can't remember if I mentioned it in that thread, but I drove my buddy's 2024 Silverado 3500 gasser and his does the same thing. I'll also probably mention it to my dealer before my warranty is up just to have it documented, but my guess is this will be another "normal" GM characteristic. 

[No F-bdy Bs]

38 minutes ago, BuckWallace said:

Let us know what your dealer says. I can't remember if I mentioned it in that thread, but I drove my buddy's 2024 Silverado 3500 gasser and his does the same thing. I'll also probably mention it to my dealer before my warranty is up just to have it documented, but my guess is this will be another "normal" GM characteristic. 

Right, the more I read, the more common it appears to be,for good or ill. 

It sounds like something is being engaged, and spooling up to rpm. Like a lockup being engaged? 

Whatever. Doesn't seem to be any widespread failures. 

Is it happening to the dmax guys that anyone has heard? 

[lineman1234]

Very normal, mine from new, 2024 3500, and now 24,000ish miles on it still does it. Its the nature of the beast 10 speed. May very with some, but mine empty, every time, changes with temp, to louder when cold, a little less when warm. Nothing when towing. 

 

Craploads of posts on it, gas and diesel. 

[bruceb58]

Mine does the exact same thing. Sounds like a turbo spinning up. When I took it into the dealer for other issues, I had them listen to it and they said nothing is wrong. They did tell me there is an issue with the transmission fluid pump on some but it is WAY louder and heard no matter what gear you are in.