New 2500 issues

[Ballaz]

Bought a new Sierra 2500 (Volcanic Red) and I had some concerns that I felt this community could edify me on prior to me taking it to the dealer and they causing more problems.

1. The truck seems to have an unstable idle after warmup and I can feel some shake in the driver's seat. I hooked it up to my scanner and it fluctuates between 530-580 rpm.

2. I hear a whistle noise around 30-50mph that is not present 0-30mph or greater than 50mph.

3. I hear a low hard to describe noise from the interior steering column slow/low speed turns. ot almost sounds like its comimg from the vents but, the hvac is off. Present in drive and park. It's slightly lower than the sound of the HVAC fans and not present when the wheel is not being turned. Almost like whisper quiet paper crumbling.

All these symptoms are either not present or milder on other trucks I have driven with the same powertrain. As stated above; if it's normal variation; I don't want the dealer to try and fix what's not broken. However, I don't want it to linger if it can be remedied.

 

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[gemarsh]

Welcome.

How miles? Is it broken in yet?

 

[Ballaz]

1200 miles. Changed oil @ 1k. Checked transmission fluid to ensure it was not over or underfilled.

 

[Ballaz]

Greased 9 zerk fittings

 

[gemarsh]

I'd wait a bit before taking it to the dealer for the rough idle issue. Tranny isn't learnt yet.

Whistle sound go away with the hvac turned off?

Don't know what to say about the steering noise.

 

[Ballaz]

I'd wait a bit before taking it to the dealer for the rough idle issue. Tranny isn't learnt yet.

Whistle sound go away with the hvac turned off?

Don't know what to say about the steering noise.

Whistle sound present no matter what. I tried cycling between 4 hi, low, and auto. Always present. My worry is the transmission already failing on a new 70k truck.smh

 

[BuckWallace]

Welcome!

1. Not sure there.

2. Do you have a diesel or gas version? This could be a couple things, but the reaction gearsets in gears 3-6 and 8-10 can make a whining noise commonly heard around 30 mph, most prominently in gears 4-5. See TSB 24-NA-262. I ask diesel vs gas because it can likely be heard more clearly with the quieter gas engine. My 2024 gasser also had a whistling noise around 20-30 mph, but that was caused by a loose exhaust flange right after the manifold causing the exhaust to make a whistling noise.

3. This is probably the power steering pump whine/rush that we HD owners are so fond of. Once the truck is under load/throttle the noise goes away, but when idling and at low RPMs you can hear the fluid "rushing" noise coming from behind the driver side air vent.

 

[24Titanium3500]

My gas 6.6 idling. 39k miles, been driving it allllll day, so she's warm!

 

[Ballaz]

Welcome!

1. Not sure there.

2. Do you have a diesel or gas version? This could be a couple things, but the reaction gearsets in gears 3-6 and 8-10 can make a whining noise commonly heard around 30 mph, most prominently in gears 4-5. See TSB 24-NA-262. I ask diesel vs gas because it can likely be heard more clearly with the quieter gas engine. My 2024 gasser also had a whistling noise around 20-30 mph, but that was caused by a loose exhaust flange right after the manifold causing the exhaust to make a whistling noise.

3. This is probably the power steering pump whine/rush that we HD owners are so fond of. Once the truck is under load/throttle the noise goes away, but when idling and at low RPMs you can hear the fluid "rushing" noise coming from behind the driver side air vent.

Thanks for the feedback. 6.6 gas. I'll have the dealership take a look at the exhaust as well.