Belt squeal (?) on cold start up on 2024 Chevy 2500HD 6.6L Gasser

MudMonkey · June 21

I am having the same issue with my truck. It is a 24 2500 with 7k miles and noticed the belt squeal/chirp at around 1000 miles.

The first visit they checked the pulleys and didn’t find anything.

the dealer has called in for support to the higher ups.

The service manager had mentioned they might look into the intake/throttle body for the noise.

I asked them if the noise is there with the belt off. Apparently they didn’t check that out. If it still makes the noise with the belt off, it might be related to the air intake system.

It has been to the dealer twice and they have not come up with a solution.

i have a third visit scheduled on the first to replace the driver seat motor and they will investigate further on the squeal.

Phillyred · June 27

I just picked mine up today from the dealership for the exact same issue . They changed the idler pulley and belt but issue still remains . I’m thinking it’s coming from the transmission . Gonna take it back tomorrow and have them keep working it . Very frustrating since this is a brand new truck and this will be the third time back to the dealer for the same issue . First time they said they could not duplicate it .

UWSkier · June 27

I don't think it's belt related given it goes away under engine load and at higher RPMs. I'm thinking it's:

Exhaust leak from a flange somewhere

Valvetrain noise

Injector noise

MudMonkey · June 27

Mine will go back in on Monday. The tech did check if the noise was still there with the belt off and it was.

Dealership is leaning more towards something with the air flow on the intake is the culprit.

MudMonkey · July 1

Dealership says it is the starter and have one ordered to change it out. Apparently it has been more common on the half tons pickups.

I will post an update when the starter gets put in.

Another JR · July 1

55 minutes ago, MudMonkey said:

Dealership says it is the starter and have one ordered to change it out. Apparently it has been more common on the half tons pickups.

I will post an update when the starter gets put in.

Did they say how/why the starter makes the noise? It should be disengaged from the flywheel and just sitting when the truck is running.

UWSkier · July 1

41 minutes ago, Another JR said:

Did they say how/why the starter makes the noise? It should be disengaged from the flywheel and just sitting when the truck is running.

Weird... harmonic vibration in the bendix maybe? Looking forward to the report back!

Tempted to throw mine up on the ramps and put my mechanic's stethoscope on the starter.

Edited July 1 by UWSkier

MudMonkey · July 1

Mechanic said he listened to the starter with a stethoscope to confirm it. Maybe it is the same starter as the half tons and has something to do with auto start stop feature?

UWSkier · July 2

17 hours ago, MudMonkey said:

Mechanic said he listened to the starter with a stethoscope to confirm it. Maybe it is the same starter as the half tons and has something to do with auto start stop feature?

I noticed yesterday when it was 110f out and my truck was hot, if I'd shut it off, then restart it, it'd only make the noise for a few seconds right after starting... maybe...

mrjulian416 · August 1

On 7/1/2024 at 6:20 PM, MudMonkey said:

Mechanic said he listened to the starter with a stethoscope to confirm it. Maybe it is the same starter as the half tons and has something to do with auto start stop feature?

Mudmonkey, did the new starter solve the issue?

Joe97281 · August 1

Mine squeals on cold startup if i press the brake too hard. If anyone has a cold start noise, but not while driving, try less pressure on the pedal.

MudMonkey · August 2

I am still waiting on a starter to come in. Dealership is hoping they can get one by the 12th.

they tried finding one from another dealership and apparently no one is letting them go if they have one.

Edited August 2 by MudMonkey

Terry Nagy · August 5

I have 2024 6.2L Trailboss making the exact same noise as your video. Literally identical. Dealer said they couldnt here it (LOL, I hear it all the time.) Any solutions I can throw back at them on this?

MudMonkey · August 6

6 hours ago, Terry Nagy said:

I have 2024 6.2L Trailboss making the exact same noise as your video. Literally identical. Dealer said they couldnt hear it (LOL, I hear it all the time.) Any solutions I can throw back at them on this?

I can hear the noise every time I give a quick blip of the throttle when it is park.

Service department said there is TSB for a starter noise. I don’t know the TSB number.