Has anyone experienced this engine noise '21 or '22?

[mb1500]

@Z7122 , what is the DFM that you're referring to? I tried L9, and like you, the noise disappears. I am by no means well versed in the technical or mechanical aspects here. I'm struggling to understand why the injectors would make the noise in Drive, but not in L mode. Also trying to figure out how to make the dealer understand and agree to diagnose and correct it.

@Doubeleive , I don't know what made me ask if it would shift through the gears normally. I guess because I had never tried L mode on this vehicle. It was a stupid question, LOL.

In older models going back to the 6 speed I believe, tow/haul or M5 disables the AFM on earlier models and it seems that M9 will disable DFM on 21+.

If the noise goes away when in L9 and not in D and the noise is most likely associated with the DFM system. This system shuts off cylinders at will and can run on any combination of the 8 cylinders because all of them are setup this way.

 

[chrisgiles]

Interesting regarding the DFM...I wonder if there's a way to permanently disable that, and if the dealer would be willing to do it (I doubt it).

 

[WalleyeMikeIII]

In older models going back to the 6 speed I believe, tow/haul or M5 disables the AFM on earlier models and it seems that M9 will disable DFM on 21+.

If the noise goes away when in L9 and not in D and the noise is most likely associated with the DFM system. This system shuts off cylinders at will and can run on any combination of the 8 cylinders because all of them are setup this way.

Tow/Haul did not disable AFM on my 2013 Suburban...often it would go to V4 mode when coasting into town and my boat behind me.

 

[Blackcar]

Interesting regarding the DFM...I wonder if there's a way to permanently disable that, and if the dealer would be willing to do it (I doubt it).

It's just mechanical work and it has nothing to do with emissions and if vehicle is out of warranty, they probably would do it for so much an hour, but you can probably find a good mom and pop shop that would do at a better price

 

[mb1500]

Tow/Haul did not disable AFM on my 2013 Suburban...often it would go to V4 mode when coasting into town and my boat behind me.

Interesting, I thought the tow/haul disabled it but wouldn’t know. I always get it disabled via tune.

 

[Erik23]

I just had my wife’s 22 Denali 6.2 in for the exact same issue. It also makes the same noise on cold start, especially when you put it into gear. Dealers hears the sound but after having the car for 5 days says they talked to gm and they advised it’s normal and there is nothing to fix. This is insane!

 

[Rickd11]

I just had my wife’s 22 Denali 6.2 in for the exact same issue. It also makes the same noise on cold start, especially when you put it into gear. Dealers hears the sound but after having the car for 5 days says they talked to gm and they advised it’s normal and there is nothing to fix. This is insane!

Same thing happened to me. For the first 1500 miles it didn't make any noise on cold start, then I started noticing it a little, kinda like a belt or pulley or exhaust leak. I can't put my finger on it. But it's progressively gotten louder to the point where it's embarrassing to start out in public now. Dealer says it's normal operation. It's ridiculous.

 

[0x_2a]

My brand new 23 Yukon Denali Ultimate has this sound. Asked about it on the lot, they said they all do that under 1500 RPM. Slightly jerky 2nd gear on acceleration too (pedal 30-40% down). Will poke around, sounds more like exhaust system than belts to me.

 

[ACCER123]

I have a 23 Suburban 5.3. Recently start to notice the same sound from the op video when the truck drop speed to approximately 15mph, couldn't make out what is it yet

 

[chrisbusnut]

I've been driving in L9 for the past few months, and there is no noise unless I forget to manually switch to L9 and leave it in drive. It's a pain to have to repeatedly press the L and then + buttons until I'm in 9th gear each time I switch into Drive, but it's better than hearing the injector noise. So it must be related to the cylinder deactivation feature. I agree that it's embarrassing, not to mention extremely frustrating and disappointing, especially considering what I spent on this vehicle.

 

[Erik23]

I've been driving in L9 for the past few months, and there is no noise unless I forget to manually switch to L9 and leave it in drive. It's a pain to have to repeatedly press the L and then + buttons until I'm in 9th gear each time I switch into Drive, but it's better than hearing the injector noise. So it must be related to the cylinder deactivation feature. I agree that it's embarrassing, not to mention extremely frustrating and disappointing, especially considering what I spent on this vehicle.

Do you get it at startup as well? That is what is bugging my wife and I the most.

 

[WalleyeMikeIII]

I get squeaky, rhythmic noise at startup. To me sounds like a squeaky pulley or belt noise. Goes away after about 10-15s, worst on cold starts. Initially was maybe 1s after startup, now 10-15. Reported it early to dealer. And again at 8600 miles. Now at 10,100. They said it’s “normal.” Meaning many Yukons and Sierras do it.

Frustrates me too, but other than the noise, no ill effects yet.

 

[tom3]

Son ran into this on his pickup a while back. Constant chirp. New belts, clean pulleys, nothing worked. We took a real close look at the pulleys and one of them had a raised ridge across it, parting line in the press or something. We filed that smooth and it quieted it down completely. Worth a look.

 

[Blackcar]

Son ran into this on his pickup a while back. Constant chirp. New belts, clean pulleys, nothing worked. We took a real close look at the pulleys and one of them had a raised ridge across it, parting line in the press or something. We filed that smooth and it quieted it down completely. Worth a look.

Did he say which pulley he found this on?

 

[tom3]

No, but I'll ask him when I see him next.

 

[Z15]

V8 Engine Sounds

The 6.2L V8 engine (RPO L87) and 6.6L V8 engine (RPO L8T) may produce several different sounds under various conditions on some 2019-2023 Silverado 1500, Silverado 2500/3500, Tahoe, Suburban, Sierra 1500, Sierra 2500/3500, Yukon and Escalade models. Some of these sounds, which may be described as a chirp, squeak or sputter, are normal conditions based on the current operation of the engine.

To help clarify the sounds and their source, Bulletin #22-NA-218 includes several examples of the sounds as well as when they typically occur, such as when the spark timing is retarded. The sounds are more noticeable on the 6.2L engine (L87) and 6.6L engine (L8T) (Fig. 8) than on the 5.3L engine (RPO L84).

Keep in mind that engine sounds will be more prominent when the vehicle is next to a reflecting surface, including walls and guardrails or when another vehicle is in an adjacent lane while driving.

Catalyst Light Off – Occurs on start when spark retard is required for catalyst rapid warm up and may last approximately 30 seconds. Catalyst rapid warm up is not triggered on all starts. The vehicle generally must have sat for an hour or more.

Engine Restart – Following complete engine shutdown coasting down through approximately 14 MPH (22 km/h), the noise will only last for about 1 second. Spark is retarded to prevent engine overspeed/torque bump.

Auto-Start – At the end of an engine stop/start shutdown, the noise will last for less than 1 second. Spark is retarded to prevent engine overspeed/torque bump.

Throttle Blip – Light throttle blip in Park/Neutral. The sound is rarely noticed and may be hard to reproduce. Spark is retarded to prevent engine overspeed.

Do not attempt to compare these sounds to similar vehicles as the noise may be different from one vehicle to another, which could lead to unnecessary repairs. These sounds are a normal operating characteristic of the engine and any repairs should not be performed. Replacing the engine or internal components for these sounds will not reduce or eliminate the condition.

For more information, and to listen to the sound clip examples, refer to Bulletin #22-NA-218.

 

[WalleyeMikeIII]

V8 Engine Sounds

Would love to hear the samples!

 

[Erik23]

V8 Engine Sounds

Wow, yeah pretty much describes it to a T. Wonder why my 6.2 corvette c8 doesn’t experience any of this.

 

[chrisbusnut]

Do you get it at startup as well? That is what is bugging my wife and I the most.

I don't really hear the noise at start-up, unless it restarts from the Auto-Stop. Putting the transmission into L9 disables the Auto-Stop. It does make quite a bit of noise upon cold start up, with both higher RPMs and what sounds like injector ticking, but I'm not as concerned about that. I just think that GM's response to this is total BS.

 

[Deuce16GMCs]

Gentleman,

I have 2023 6.2 Tahoe.

It suffers from the GM 6.2 Squeal Chirp.

It squeals when stopping at 14 miles per hours (this one can be cancelled by driving in L9 to deactivate the DFM).

It squeals during every gear shift (regardless of L9). Although very faint.

It squeals when accelerating from the mid 30's to mid 40's (regardless of L9)

It squeals when cruising on the highway in the low 70's (regardless of L9).

Have any you that have the squealing/chirp experienced it when cruising gentle around 39-40 mph and moderately accelerate back up to 45-48 mph. This happens in D or L9 so it's not a part of the DFM.

Your help would be greatly appreciated!