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2014+ AFM (Active Fuel Management)

Ron.s

By Ron.s
in Engines & Drivetrain

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BMyers Enthusiast

BMyers

Posted
Posted
17 hours ago, Grumpy Bear said:

Bob, read that post carefully. 1.) First post 2.) He turned off both AFM and DOD. Really? C'mon man. They are the same thing 3.) He's using he DIC to report some fiction on mileage. It's physically impossible.  4.) Herky Jerky? LOL....not. 5.) Sounding bad. I know I'm half deaf but if the factory exhaust is in play you are hard pressed to hear it under any conditions. 6.) IF and it's a big if, you could HEAR ping then your knock sensors are not working as they should. 

 

Internet is full of this crap. It's a full story below you brother. 

So that's pretty interesting, I'm a 30 year tech, run a shop so it's my own experience.  Diablo has a way to disable DOD and AFM seperately, my fuel mileage is real, what difference is the first post are you wanting me to stay out?  Anyway my truck runs great, bought it new, 2018 Sierra SLT 5.3, also run a catch can to remove oil vapors.   The mods I did was mostly for preserving the engine and my investment, the improved performance is fun and great, and the mileage was unexpected.  I don't have any pinging btw so maybe up the tune to the Diablo and see how it goes.

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oldmann
oldmann

Why are people so concerned about this topic. I do not understand it. Just drive it. End of story. And yes, even if you can't figure out why the truck has it, it is to save fuel.

pm26
pm26

No, it does not. Not even close. The only Cadillacs that possibly exceeded the weight of 2014 GM crew cab 1500 4x4 pickups were the old land yachts (1976 and older) models. I believe that a 1976 Ca

seamonster
seamonster

Whats up with the name calling?   Cant you see we agree----the AFM feels like a gear shift!   Many people want 6 and 8 speed tranny and then complain they can feel AFM. That is what I dont unders

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Grumpy Bear Senior Enthusiast

Grumpy Bear

Posted
Posted
2 hours ago, BMyers said:

So that's pretty interesting, I'm a 30 year tech, run a shop so it's my own experience.  Diablo has a way to disable DOD and AFM seperately, my fuel mileage is real, what difference is the first post are you wanting me to stay out?  Anyway my truck runs great, bought it new, 2018 Sierra SLT 5.3, also run a catch can to remove oil vapors.   The mods I did was mostly for preserving the engine and my investment, the improved performance is fun and great, and the mileage was unexpected.  I don't have any pinging btw so maybe up the tune to the Diablo and see how it goes.

DOD and AFM are the same thing.

 

AFM or Active Fuel Management is the GM TRADEMARK NAME for what everyone else calls displacement on demand DOD. 

BMyers Enthusiast

BMyers

Posted
Posted
53 minutes ago, Grumpy Bear said:

DOD and AFM are the same thing.

 

AFM or Active Fuel Management is the GM TRADEMARK NAME for what everyone else calls displacement on demand DOD. 

So grumpy I get that point so get mine.  It works and your dick way of discussing this isn’t cool.  I’m just offering real life experience and results that I’ve been pleased with.  Acknowledge that with your stinging criticism.   Btw your internet attack sidelines a real guy just looking for info while dicks like you lurk around to pounce with your digital knowledge.  Bye.  Your type ruins these forums.  

  • Haha 1
James Dink Enthusiast

James Dink

Posted
Posted
3 hours ago, BMyers said:

So that's pretty interesting, I'm a 30 year tech, run a shop so it's my own experience.  Diablo has a way to disable DOD and AFM seperately, my fuel mileage is real, what difference is the first post are you wanting me to stay out?  Anyway my truck runs great, bought it new, 2018 Sierra SLT 5.3, also run a catch can to remove oil vapors.   The mods I did was mostly for preserving the engine and my investment, the improved performance is fun and great, and the mileage was unexpected.  I don't have any pinging btw so maybe up the tune to the Diablo and see how it goes.

do you mean dod and vvt? lol 

BMyers Enthusiast

BMyers

Posted
Posted
11 minutes ago, James Dink said:

do you mean dod and vvt? lol 

No I get what your saying and grumpy is probably correct that in gm language dod and afm are the same but in the Diablo tuner it is 2 separate functions to choose.  I turned both of them off.  Vvt is probably part of the programming in the tune for performance though.    Diablo tuners have options for many settings including timing and fuel mixture and shift pressures but nothing for vvt.  That would be interesting though.  

Grumpy Bear Senior Enthusiast

Grumpy Bear

Posted
Posted
1 hour ago, BMyers said:

So grumpy I get that point so get mine.  It works and your dick way of discussing this isn’t cool.  I’m just offering real life experience and results that I’ve been pleased with.  Acknowledge that with your stinging criticism.   Btw your internet attack sidelines a real guy just looking for info while dicks like you lurk around to pounce with your digital knowledge.  Bye.  Your type ruins these forums.  

:crackup:

 

You do know what Trademark means, right?

Is this where I say something like, "sticks and stones.....?"

Really? Name calling?

My type?

:wtf:

 

You want to be acknowledged? Offer correct information!

 

j-ten-ner Senior Enthusiast

j-ten-ner

Posted
Posted
2 hours ago, BMyers said:

... and your dick way of discussing this isn’t cool. ...Acknowledge that with your stinging criticism. ...your internet attack sidelines a real guy...while dicks like you lurk around to pounce with your digital knowledge. ...Your type ruins these forums.  

I guess you haven't been around on this forum for very long?

 

43 km shy of 200,000km on my truck as of today.

AFM disabled since day one.

Oil consumption is getting less over time. No idea why.

No knocking lifter or any other drive train related problems so far ( I don't expect any 'til 250,000km, just my expectations of a modern vehicle).

So, yes, if you don't worry too much about fuel economy, disable the DOD and shive on.

 

so long

j-ten-ner

BMyers Enthusiast

BMyers

Posted
Posted
20 minutes ago, j-ten-ner said:

I guess you haven't been around on this forum for very long?

 

43 km shy of 200,000km on my truck as of today.

AFM disabled since day one.

Oil consumption is getting less over time. No idea why.

No knocking lifter or any other drive train related problems so far ( I don't expect any 'til 250,000km, just my expectations of a modern vehicle).

So, yes, if you don't worry too much about fuel economy, disable the DOD and shive on.

 

so long

j-ten-ner

I agree, that is my experience too.  My mileage is better and runs great.  

Grumpy Bear Senior Enthusiast

Grumpy Bear

Posted
Posted (edited)

178,637 km or 111,000 miles with AFM active without a single issue. Fact is I've gone out of my way to keep it on more. 

 

You guys do know that failed lifters happen on NON-DOD cylinders to,  right? Shutting it off wont stop those from happening. 

Edited by Grumpy Bear
j-ten-ner Senior Enthusiast

j-ten-ner

Posted
Posted

Reason #1 for disabling AFM was for my own comfort.

Couldn't stand the transition between V4 and V8. Especially in combination with the 6 speed.

 

so long

j-ten-ner

JimCost2014 Senior Enthusiast

JimCost2014

Posted
Posted
On 3/12/2020 at 4:12 PM, BMyers said:

your dick way of discussing this isn’t cool.

You have met the welcome wagon, pretty good response.

 

Keep asking questions, plenty of help and you will find the answers you are looking for.

 

What year is your 67-72?

Grumpy Bear Senior Enthusiast

Grumpy Bear

Posted
Posted
3 hours ago, j-ten-ner said:

Reason #1 for disabling AFM was for my own comfort.

Couldn't stand the transition between V4 and V8. Especially in combination with the 6 speed.

 

so long

j-ten-ner

If the display didn't tell me what mode it was in I wouldn't know. Funny that. 

j-ten-ner Senior Enthusiast

j-ten-ner

Posted
Posted

Maybe the transition from v6 to v4 is less noticeable to begin with, than the transition from v8 to v4.

Maybe they've changed the programming between 2013 and 2015.

Maybe my truck, or yours, is one of those exceptions.

 

I think what makes the whole thing even worse, is when you live in a hilly area.

 

so long

j-ten-ner

KARNUT Senior Enthusiast

KARNUT

Posted
Posted

When this thread started I had my 14. I tuned out the V-4 and Hwy mileage change was negligible at 70 and up speeds. I had exhaust for awhile and the drone was awful. I noticed the change in every cylinder deactivation vehicle I’ve been in. My recent purchase of my 02 Avalanche I had a chance to compare. My combination driving has produced 16 MPG, 2 off from my 14. My Hwy should be 20 2-3 off from my 14. That’s with a 373 gear. So for the few miles per gallon, a transmission that cost two times to rebuild and a host of engine add ons to fail. One of my biggest joys of being a retired car guy is I can choose to say no to the latest junk technology.


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truckguy82 Senior Enthusiast

truckguy82

Posted
Posted
On 3/13/2020 at 11:48 PM, Grumpy Bear said:

If the display didn't tell me what mode it was in I wouldn't know. Funny that. 

When justin from blackbear tuned my truck in person (i was driving he was tuning in passenger seat)

 

he said some trucks have a noticeable issue with it and some are smooth as butter. I would imagine not many people on earth have been in a larger number of trucks and paid attention to the switching action.

 

Since I never notice mine, before he told me that I thought everybody complaining about afm switchover were whining grade school girls.

 

 

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