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2021 Silverado DFM/AFM

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shanemoon Enthusiast

shanemoon

Posted
Posted
On 6/6/2021 at 1:44 PM, EricTheRed said:

Can the dealership do a DFM delete for those of us who don’t want the added noises and shuttering of this “seamless” system? 

???

DFM is not noticeable at all. AFM maybe, but not DFM. You'll never know when it's doing it.

You talking about auto start/stop?

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EricTheRed Enthusiast

EricTheRed

Posted
Posted
On 1/5/2022 at 7:18 PM, shanemoon said:

???

DFM is not noticeable at all. AFM maybe, but not DFM. You'll never know when it's doing it.

You talking about auto start/stop?


I can’t tell if you’re joking or just can’t hear your engine well enough, but either way thanks for the laugh.

voided3 Enthusiast

voided3

Posted
Posted
12 hours ago, EricTheRed said:


I can’t tell if you’re joking or just can’t hear your engine well enough, but either way thanks for the laugh.

Agreed, cruising at specifically 31 MPH our truck sounds like a helicopter with DFM active and it feels like a parachute is chained to the hitch when it activates cruising at 55-65 MPH, plus all of the vibration at any speed when it's active. Disabling the system by driving in L7 is the only tolerable way for me to drive it.

shanemoon Enthusiast

shanemoon

Posted
Posted (edited)
14 hours ago, voided3 said:

Agreed, cruising at specifically 31 MPH our truck sounds like a helicopter with DFM active and it feels like a parachute is chained to the hitch when it activates cruising at 55-65 MPH, plus all of the vibration at any speed when it's active. Disabling the system by driving in L7 is the only tolerable way for me to drive it.

 

On 1/7/2022 at 6:47 PM, EricTheRed said:


I can’t tell if you’re joking or just can’t hear your engine well enough, but either way thanks for the laugh.

Dynamic and individualized cylinder deactivation is not perceivable on any vehicle that has it. Or at least not the 20-30 I’ve driven that have it. Most other car reviewers/journalists would say the same. 
AFM and similar technologies from other manufacturers on the other hand, is very noticeable.


I cannot feel or hear DFM on my Silverado even if I try. And I work on cars for a living.
There are plenty of other forum posts that also echo is…that DFM is seamless and it was a huge improvement from AFM where you could feel and hear it every time. 

Either you guys just have a bad batch, or you actually have AFM trucks and you think you have DFM. Might want to check your RPO codes. L84 is DFM. L83 is AFM. 

Edited by shanemoon
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BossTaco2020 Enthusiast

BossTaco2020

Posted
Posted
On 1/8/2022 at 10:53 PM, shanemoon said:

 

Dynamic and individualized cylinder deactivation is not perceivable on any vehicle that has it. Or at least not the 20-30 I’ve driven that have it. Most other car reviewers/journalists would say the same. 
AFM and similar technologies from other manufacturers on the other hand, is very noticeable.


I cannot feel or hear DFM on my Silverado even if I try. And I work on cars for a living.
There are plenty of other forum posts that also echo is…that DFM is seamless and it was a huge improvement from AFM where you could feel and hear it every time. 

Either you guys just have a bad batch, or you actually have AFM trucks and you think you have DFM. Might want to check your RPO codes. L84 is DFM. L83 is AFM. 

Exactly! I can't tell when DFM activates on my 5.3 w/10spd trans. However I do feel vibration, but that's from the crappy DuraTracs that I can't wait to get rid of. I think people just want to hate on any new technology and then there's the "I pAiD fOr A v8 and mUh FrEeDuMz!!!" people...

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KARNUT Senior Enthusiast

KARNUT

Posted
Posted
33 minutes ago, BossTaco2020 said:

Exactly! I can't tell when DFM activates on my 5.3 w/10spd trans. However I do feel vibration, but that's from the crappy DuraTracs that I can't wait to get rid of. I think people just want to hate on any new technology and then there's the "I pAiD fOr A v8 and mUh FrEeDuMz!!!" people...

If you want all the potential failures from the extra technology that gives you 1 mile per gallon at best. Well bless your heart. By the way the 1 mile per gallon is from GM. Every cylinder deactivation vehicle I’ve been in I could feel it and hear it. I’ll never own one. Yup one of those.

Carlos Eduardo Silva Enthusiast

Carlos Eduardo Silva

Posted
Posted

This week I bought a 2022 LTZ (that is the LTD 2021 LOL) and on the Window Stick it doesn't tell anything about the DFM but I also checked my RPO codes and I didn't see the YK9 that someone said that it is the code for engine that has the DFM disabled.

So, I'm not sure 100% sure if my L84 engine has or not the DFM. I hope not.....

 

 

shanemoon Enthusiast

shanemoon

Posted
Posted
6 hours ago, Carlos Eduardo Silva said:

This week I bought a 2022 LTZ (that is the LTD 2021 LOL) and on the Window Stick it doesn't tell anything about the DFM but I also checked my RPO codes and I didn't see the YK9 that someone said that it is the code for engine that has the DFM disabled.

So, I'm not sure 100% sure if my L84 engine has or not the DFM. I hope not.....

 

 

Your truck would have the YK9 code if it was some of the models that came without DFM due to the semi-conductor issues. If that is not on your RPO list, an L84 engine has DFM.

shanemoon Enthusiast

shanemoon

Posted
Posted
11 hours ago, KARNUT said:

If you want all the potential failures from the extra technology that gives you 1 mile per gallon at best. Well bless your heart. By the way the 1 mile per gallon is from GM. Every cylinder deactivation vehicle I’ve been in I could feel it and hear it. I’ll never own one. Yup one of those.

Fair enough...but with that attitude we'd still be using engines from the 70's without any electronics....getting 200HP out of a 8 liter, V8 and getting 7MPG.

Advancement takes trial and error.

AFM and most other "banked" cylinder deactivation were proven to be inferior, so they've developed new dynamic systems that have proven to be very reliable.

KARNUT Senior Enthusiast

KARNUT

Posted
Posted
25 minutes ago, shanemoon said:

Fair enough...but with that attitude we'd still be using engines from the 70's without any electronics....getting 200HP out of a 8 liter, V8 and getting 7MPG.

Advancement takes trial and error.

AFM and most other "banked" cylinder deactivation were proven to be inferior, so they've developed new dynamic systems that have proven to be very reliable.

I don’t have any problems with real advancement. The Frankenstein engines do very little for the costumers. All that extra hardware for 1 mpg. I was interested in the blown 4 cylinder. The had to do cylinder deactivation in that too. My first car was a rotary Mazda. I had a 5.7 GM diesel. 7.3 and 5.9 diesel. The redesign 94 Ram diesel. First in my town with the 94 impala ss and 06 trailblazer ss. New stuff no problem. Frankenstein engines. NO. I buy a V-8 that’s what I want, no tricks. 

shanemoon Enthusiast

shanemoon

Posted
Posted (edited)
19 minutes ago, KARNUT said:

I don’t have any problems with real advancement. The Frankenstein engines do very little for the costumers. All that extra hardware for 1 mpg. I was interested in the blown 4 cylinder. The had to do cylinder deactivation in that too. My first car was a rotary Mazda. I had a 5.7 GM diesel. 7.3 and 5.9 diesel. The redesign 94 Ram diesel. First in my town with the 94 impala ss and 06 trailblazer ss. New stuff no problem. Frankenstein engines. NO. I buy a V-8 that’s what I want, no tricks. 

Every little thing has gotten us to where we are now. 1MPG doesn't seem like alot...but over the course of a year, conservatively that's anywhere from 1300-2000 miles of extra range. Or $400 in gas savings. (also it looks like the L84, 8SPD with DFM delete takes a 2MPG hit to city rather than 1MPG)

And as far as technology goes...it takes small increments to make progress. We don't just jump from getting 7MPG to 25MPG in one generation of engines. It takes time and compounding change.

 

I also don't know that I'd consider cylinder deactivation a "frankenstein engine" lol....the weird Ram E-Torque thing for sure, but cylinder deactivation is mainly software.

 

Almost every car in the coming future will have some sort of cylinder deactivation. Heck they even do it in the Ford GT and most supercar/hypercars now with V8's, V10's and V12's....it just is what it is. It's a pretty proven technology at this point.

 

And it is what has kept GM from going to a hybrid or turbo V6 like Ford and others have. So take your pick....turbo/hybrid V6 or V8 with cylinder deactivation....lol

Edited by shanemoon
KARNUT Senior Enthusiast

KARNUT

Posted
Posted
7 hours ago, shanemoon said:

Every little thing has gotten us to where we are now. 1MPG doesn't seem like alot...but over the course of a year, conservatively that's anywhere from 1300-2000 miles of extra range. Or $400 in gas savings. (also it looks like the L84, 8SPD with DFM delete takes a 2MPG hit to city rather than 1MPG)

And as far as technology goes...it takes small increments to make progress. We don't just jump from getting 7MPG to 25MPG in one generation of engines. It takes time and compounding change.

 

I also don't know that I'd consider cylinder deactivation a "frankenstein engine" lol....the weird Ram E-Torque thing for sure, but cylinder deactivation is mainly software.

 

Almost every car in the coming future will have some sort of cylinder deactivation. Heck they even do it in the Ford GT and most supercar/hypercars now with V8's, V10's and V12's....it just is what it is. It's a pretty proven technology at this point.

 

And it is what has kept GM from going to a hybrid or turbo V6 like Ford and others have. So take your pick....turbo/hybrid V6 or V8 with cylinder deactivation....lol

Turbo hybrid V-6. 

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