Cylinder deactivation for the 2021-2023's?

[Deuce16GMCs]

Does anyone know if any company makes an active fuel management cylinder deactivation disabling device for the current model year, 2021 through 2023?

 

[B-train]

Not sure on that one. Depending on what build date you are looking at, I may have been deleted from the factory. I know 1500 trucks from May 21 were factory deleted. Maybe it carried over to the SUV line too?

You have to see the build sheet or window sticker to know.

 

[Deuce16GMCs]

My 2023 does have cylinder deactivation. It squeals every time it's changing from four-cylinder to eight cylinder.

I know range AFM makes the deactivation devices to disable the fuel management, but they don't make it for the 21 22 or 23.

 

[StephenPT]

My 2023 does have cylinder deactivation. It squeals every time it's changing from four-cylinder to eight cylinder.

I know range AFM makes the deactivation devices to disable the fuel management, but they don't make it for the 21 22 or 23.

DFM is used in the '21+ SUVs and it's a much more sophisticated system than AFM. Each cylinder is capable of being turned off and multiple different patterns of which cylinders are on or off.

GM’s Dynamic Fuel Management Technology | General Motors

With GM's Dynamic Fuel Management Technology, engines work at optimal mix of performance and fuel efficiency. Click to learn about this revolutionary system.

news.gm.com

 

[WalleyeMikeIII]

Thus far, the ECM of this vehicle architecture has not been able to be tuned…GM has it locked down pretty good.

 

[Deuce16GMCs]

Thus far, the ECM of this vehicle architecture has not been able to be tuned…GM has it locked down pretty good.

That's what I'm seeing. Range AFM says they still trying to decide if DFM almost 3 years later.

Hoping someone figured it out, but doesn't look like it's going to happen.

 

[WalleyeMikeIII]

Honestly, not sure why anyone wants to deactivate it…not clear to me it would improve lifter life. It’s completely transparent as a driver, I never even know if anything is deactivated or not. So, just drive the thing and enjoy.

 

[Deuce16GMCs]

Honestly, not sure why anyone wants to deactivate it…not clear to me it would improve lifter life. It’s completely transparent as a driver, I never even know if anything is deactivated or not. So, just drive the thing and enjoy.

My 2023 6.2 Tahoe squeals when it shifts between V4/V8.

If I drive in L9 (9th gear) the truck is completely silent.

2 dealers have now told me that squeals, chirping, rumbles, etc because of the DFM is normal.

I've driven 5 Tahoe/Suburban/Yukon combos and none have the squealing I have. My company uses GM SUV for work so we have fleet.

Disabling the DFM is the option I have so my truck doesn't squeal down the road when driving through my neighborhood and parking lots.

Tahoe Squealing

Check out the video here's the time stamps. This a 2 minutes drive out of my neighborhood. It happens 10 times in 2 mins.

Keep in mind I have the driver's window open and I'm hold the phone out the window so there a bunch of wind noise. You can only imagine how it sounds as you drive past someone without the wind noise.

The loudest is at the 1:25 time stamp.

It occurs when you stopping. When it's shifting at about 30 mph. When cruising on the highway under 70 mph. When starting up from a cold start. It may not seem like it, but it loud.

:28
:51
1:00
1:12
1:25
1:36
1:44
2:07
2:14

And NONE of the noises exist with the DFM deactivated.

 

[nick14226]

My 2023 6.2 Tahoe squeals when it shifts between V4/V8.

If I drive in L9 (9th gear) the truck is completely silent.

2 dealers have now told me that squeals, chirping, rumbles, etc because of the DFM is normal.

I've driven 5 Tahoe/Suburban/Yukon combos and none have the squealing I have. My company uses GM SUV for work so we have fleet.

Disabling the DFM is the option I have so my truck doesn't squeal down the road when driving through my neighborhood and parking lots.

Tahoe Squealing

Check out the video here's the time stamps. This a 2 minutes drive out of my neighborhood. It happens 10 times in 2 mins.

Keep in mind I have the driver's window open and I'm hold the phone out the window so there a bunch of wind noise. You can only imagine how it sounds as you drive past someone without the wind noise.

The loudest is at the 1:25 time stamp.

It occurs when you stopping. When it's shifting at about 30 mph. When cruising on the highway under 70 mph. When starting up from a cold start. It may not seem like it, but it loud.

:28
:51
1:00
1:12
1:25
1:36
1:44
2:07
2:14

And NONE of the noises exist with the DFM deactivated.

I can only hear the wind, must be by speakers. Unfortunately no DFM disablers as others have said. I’ve found 2 things that seem to make it more tolerable on my ‘22 5.3, 93 octane gas and corsa exhaust. Don’t know if either could help with your noise, but you could start by temporarily clamping your exhaust flapper open to eliminate it from the equation. Not much else you can do aside from L9.

 

[Deuce16GMCs]

I can only hear the wind, must be by speakers. Unfortunately no DFM disablers as others have said. I’ve found 2 things that seem to make it more tolerable on my ‘22 5.3, 93 octane gas and corsa exhaust. Don’t know if either could help with your noise, but you could start by temporarily clamping your exhaust flapper open to eliminate it from the equation. Not much else you can do aside from L9.

Well, it's been concerned that the squeal is not present in the 5.3L. It appears to be a characteristic only of the 6.2.

I guess I picked the wrong engine.

 

[nick14226]

Well, it's been concerned that the squeal is not present in the 5.3L. It appears to be a characteristic only of the 6.2.

I guess I picked the wrong engine.

Ahh, so you’re already running 93.

If you’re up for the experiment, I’d try clamping that flapper open, or in your case with the 6.2 might be two of them. Even if the noise isn’t coming from underneath, I’d still give it a shot.

 

[chrisbusnut]

Well, it's been concerned that the squeal is not present in the 5.3L. It appears to be a characteristic only of the 6.2.

I guess I picked the wrong engine.

I'm in the same boat, and I've just given up and drive in L9. The noises that my 6.2 makes relating to DFM are frustrating and embarrassing. And, like you, I've driven at least 6 other 21/22 Tahoes/Yukons/Suburbans with the 6.2 and none of them made the noise. I wonder what Cadillac's response is when someone who has spent $120K on an Escalade comes in and demands that they get rid of the noise.

I did contact Range Technology, and they confirmed that they don't have anything yet that will work on our vehicles. I really hope they come out with something soon.

 

[Deuce16GMCs]

Unfortunately it's not going to help. There's a TSB out from November 2022 that states that 6.2 liter engines experience squeals and chirps due to the retarding of the spark and the catalyst warm up.

Apparently it affects all 2021 and newer 6.2 engines to different degrees. It would seem that mine is worse than most others.

 

[Deuce16GMCs]

I'm in the same boat, and I've just given up and drive in L9. The noises that my 6.2 makes relating to DFM are frustrating and embarrassing. And, like you, I've driven at least 6 other 21/22 Tahoes/Yukons/Suburbans with the 6.2 and none of them made the noise. I wonder what Cadillac's response is when someone who has spent $120K on an Escalade comes in and demands that they get rid of the noise.

I did contact Range Technology, and they confirmed that they don't have anything yet that will work on our vehicles. I really hope they come out with something soon.

My truck is currently at its third dealership.

The first dealer that actually tried to address it took $120,000 escalade out and said that it squealed just like mine just a bit quieter. It wouldn't let me ride with them. I just had to take their word for it.

At the second dealership I drove a 6.2 l Tahoe Premier and it also squealed at stops but not during the shifts or on the highway. It stops on squealing was dramatically quieter than mine.

The current dealership that it's at is telling me that none of their vehicles on their lot experience that squealing and that it's absolutely not normal, and that they're going to take it up with GM. Let's hope they do the right thing.

But according to the TSB there's absolutely no fix.

 

[Deuce16GMCs]

I'm in the same boat, and I've just given up and drive in L9. The noises that my 6.2 makes relating to DFM are frustrating and embarrassing. And, like you, I've driven at least 6 other 21/22 Tahoes/Yukons/Suburbans with the 6.2 and none of them made the noise. I wonder what Cadillac's response is when someone who has spent $120K on an Escalade comes in and demands that they get rid of the noise.

I did contact Range Technology, and they confirmed that they don't have anything yet that will work on our vehicles. I really hope they come out with something soon.

Here's GM's bulletin.

https://static.nhtsa.gov/odi/tsbs/2022/MC-10225749-0001.pdf

Heres a 2022 Silverado with squeal.

The bulletin says there 4 different squeals.

I won the lemon lottery have 3 of the 4.

 

[chrisbusnut]

Here's GM's bulletin.

https://static.nhtsa.gov/odi/tsbs/2022/MC-10225749-0001.pdf

Heres a 2022 Silverado with squeal.

The bulletin says there 4 different squeals.

I won the lemon lottery have 3 of the 4.

That really sucks, and i'm sorry you're going through it. Your comment regarding the 6.2 Tahoe Premier being dramatically quieter is spot on. On some of the rentals that I've driven that have the 6.2, they do make the noise, but it is MUCH quieter than mine, and honestly wouldn't bother me at all.

Best of luck, and please keep us posted!

 

[kurtibm]

Gotta love the GM rhetoric.... paraphrasing.... 'Some trucks make all kinds of different sounds...some none. Like snowflakes, no two are alike". BUT.... all these differing conditions or lack of one is normal and 'functioning as intended'. I guess they had one of joe's writers do the bulletin.

"Important: Dealers should not attempt to compare any
customer vehicles exhibiting these noises with other
similar vehicles as the noise is different from vehicle to
vehicle and this may lead to the incorrect conclusion
that the vehicle has a condition. These noises are a
normal operating characteristic of the engine. These
noises have no short- or long-term effect on the engine.
Do not attempt repairs for these noises.
Important: Replacing the engine or internal
components for this noise will not reduce or eliminate
the noise.
Please communicate to the customer that the engine is
functioning as designed and these are normal
conditions of their vehicle. Please share this
information with the customer, including a copy of this
message."

 

[AWSMBLU]

Does anyone know if any company makes an active fuel management cylinder deactivation disabling device for the current model year, 2021 through 2023?

check their website to see if one is available yet. Made by Holly

 

[Deuce16GMCs]

check their website to see if one is available yet. Made by Holly

They said it's not. GM rewrote the code for 21+. It was open source before, but now they wrote the code internally.

Range is working on breaking the code to make a model for 21+, but they don't have anything now.

They expect an update by end of year.

 

[Deuce16GMCs]

Gotta love the GM rhetoric.... paraphrasing.... 'Some trucks make all kinds of different sounds...some none. Like snowflakes, no two are alike". BUT.... all these differing conditions or lack of one is normal and 'functioning as intended'. I guess they had one of joe's writers do the bulletin.

"Important: Dealers should not attempt to compare any
customer vehicles exhibiting these noises with other
similar vehicles as the noise is different from vehicle to
vehicle and this may lead to the incorrect conclusion
that the vehicle has a condition. These noises are a
normal operating characteristic of the engine. These
noises have no short- or long-term effect on the engine.
Do not attempt repairs for these noises.
Important: Replacing the engine or internal
components for this noise will not reduce or eliminate
the noise.
Please communicate to the customer that the engine is
functioning as designed and these are normal
conditions of their vehicle. Please share this
information with the customer, including a copy of this
message."

You are spot on.

"Yes it's perfectly normal and all of our vehicles that we used our crappy components on. If you're lucky enough to be one of the ones that we used are better components on your car does not squeal. Don't compare a car with crappy components to another one with good components because they're not going to sound the same but trust us that it's perfectly normal."