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2014+ AFM (Active Fuel Management)

Ron.s

By Ron.s
in Engines & Drivetrain

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SS502 Senior Enthusiast

SS502

Posted
Posted
1 hour ago, Grumpy Bear said:

Few will be interested in this tidbit but take off in M5, when you reach 55 mph (highway only) tap in tow mode. Then select M6. The transmission stays in 5th gear as you are below the upshift point for 6th gear but as M6 is selected the AFM works. This will also work in 4th gear if you haven't reached the 5th gear upshift. I find it useful on rural highways in hilly terrain against light wind. Just stays in 5th 95% of the time and yet allows AFM on the rare flat. Downhill the fuel map shuts of the injectors anyway. When approaching a town tap back to M5 and delete tow mode. My truck is geared 3.23. Exact points will vary with gear and equipment.  

Grumpy...is your middle name Google? You Sir are a large pool of some very useful information ?

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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
3 hours ago, SS502 said:

Grumpy...is your middle name Google? You Sir are a large pool of some very useful information ?

My head is full of  junk I've learned both the easy and the hard way. I'm not afraid to experiment either. Now if I could just remember the right piece at the right time! :lol:

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3tspapat Enthusiast

3tspapat

Posted
Posted

My eAssist will disable AFM and will not shut off engine at stop using L mode set in any gear all the way up to 7th gear. If set to 8 it will go to V4 but only if 8th is engaged. 

Hillwood Enthusiast

Hillwood

Posted
Posted
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.
DILLY DILLY!!

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EIKON Enthusiast

EIKON

Posted
Posted
On 12/15/2018 at 10:14 AM, Hillwood said:

DILLY DILLY!!

Sent from my SM-G965U using Tapatalk
 

Unfortunately while it is designed to save fuel, it adds wear to items. 

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SS502 Senior Enthusiast

SS502

Posted
Posted
30 minutes ago, SMDiesel said:

Unfortunately while it is designed to save fuel, it adds wear to items. 

Unfortunately we are stuck with it. Why not at least (special order if need be) offer a DOD delete package? I’d pay extra even though I’m actually getting less in terms of “technology” any day of the week.

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EIKON Enthusiast

EIKON

Posted
Posted
On 12/19/2018 at 4:58 PM, SS502 said:

Unfortunately we are stuck with it. Why not at least (special order if need be) offer a DOD delete package? I’d pay extra even though I’m actually getting less in terms of “technology” any day of the week.

That’s part of GM meeting CAFE at the time of dosing. 

 

You up can always yank the heads and go back to real lifters ;) 

 

Unfortunately at that time you are your own warranty station. 

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SS502 Senior Enthusiast

SS502

Posted
Posted
53 minutes ago, SMDiesel said:

That’s part of GM meeting CAFE at the time of dosing. 

 

You up can always yank the heads and go back to real lifters ;) 

 

Unfortunately at that time you are your own warranty station. 

Assuming the rest of the truck makes it past factory warranty...I’ve got the same thoughts ? I will be fully retired by then and will need a hobby ?

EIKON Enthusiast

EIKON

Posted
Posted
3 hours ago, SS502 said:

Assuming the rest of the truck makes it past factory warranty...I’ve got the same thoughts ? I will be fully retired by then and will need a hobby ?

My 2015 made it 500 hard miles before I put on the kooks longtubes and a full exhaust. Added a clean air separator, modded the air intake, tuned out the AFM, and added an alchohol sensor. 

 

Ran it that way until 50k before I did the cam, converter, and swapped out the AFM lifters for LS7 style. 

 

The AFM lifters looked better than any set of AFMs that I have pulled out of 10-15k engines that had active AFM. Just turning the system off helps a bunch in my opinion. Some guys will argue otherwise. 

 

Ive seen them fail on other trucks even turned off. Not saying otherwise. But I believe turning them off early really helps. 

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SS502 Senior Enthusiast

SS502

Posted
Posted
3 minutes ago, SMDiesel said:

My 2015 made it 500 hard miles before I put on the kooks longtubes and a full exhaust. Added a clean air separator, modded the air intake, tuned out the AFM, and added an alchohol sensor. 

 

Ran it that way until 50k before I did the cam, converter, and swapped out the AFM lifters for LS7 style. 

 

The AFM lifters looked better than any set of AFMs that I have pulled out of 10-15k engines that had active AFM. Just turning the system off helps a bunch in my opinion. Some guys will argue otherwise. 

 

Ive seen them fail on other trucks even turned off. Not saying otherwise. But I believe turning them off early really helps. 

No argument here ? Since day one I’ve run mine in L7 to keep the AFM off except when I’m driving on the highway. I have maybe 5% of my total miles driven with the AFM operating and then I’d say it transitions to V4 mode about 20% of the AFM operational miles. Not what I want but it’s helping in my mind anyway ? 

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3tspapat Enthusiast

3tspapat

Posted
Posted
On 12/20/2018 at 10:09 PM, SS502 said:

No argument here ? Since day one I’ve run mine in L7 to keep the AFM off except when I’m driving on the highway. I have maybe 5% of my total miles driven with the AFM operating and then I’d say it transitions to V4 mode about 20% of the AFM operational miles. Not what I want but it’s helping in my mind anyway ? 

Hey this is what I'm also doing as well! For me it also turns off the auto shut off when I stop. 

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EPIC CAJUN Enthusiast

EPIC CAJUN

Posted
Posted (edited)

Man screw this AFM bullshit!!! I am currently waiting my truck to be fixed due to two stuck lifters from it. I am on here as we speak to research the best way to turn this "feature" OFF! I do about 90% city driving and on my daily commute, Id bet the AFM is on majority of the time. I bought a V8 for a reason. I shouldn't have to give a little gas, then wait for the computer to make its mind up before I get all 8 cylinders firing as I need more power on my daily drive.  I get this has its purpose, but in the city it seems to constantly keep this truck guessing and therefore making for a terrible driving experience. 

 

Sorry for my rant. I have the red ass still this morning and my coffee has not kicked in yet.

 

Edited by EPIC CAJUN
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KARNUT Senior Enthusiast

KARNUT

Posted
Posted
Man screw this AFM bullshit!!! I am currently waiting my truck to be fixed due to two stuck lifters from it. I am on here as we speak to research the best way to turn this "feature" OFF! I do about 90% city driving and on my daily commute, Id bet the AFM is on majority of the time. I bought a V8 for a reason. I shouldn't have to give a little gas, then wait for the computer to make its mind up before I get all 8 cylinders firing as I need more power on my daily drive.  I get this has its purpose, but in the city it seems to constantly keep this truck guessing and therefore making for a terrible driving experience. 
 
Sorry for my rant. I have the red ass still this morning and my coffee has not kicked in yet.
 

Easy boy. When engaged your transmission put in in M click you little button up to your last highest gear no V4. When your cruising and you are above 2K on your tack click up to the highest gear. That’s the cheapest way. I did a tune. Some people just leave in the next highest gear but gas mileage would suffer a bit.


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  • 3 weeks later...
joshuaandrew14 Enthusiast

joshuaandrew14

Posted
Posted

My '16 only has 19k on it and it already sounds like clockwork when I start it up most mornings. Not really sure what I'm hearing, but it doesn't sound like lifters. AFM is a great thought, but that being said, I wish it was something that the operator of the vehicle could control. Just like the auto stop feature on the wife's cruze, I HATE THAT FEATURE, pull up to a parking spot, engine stops - put in park - engine starts right back up just for me to shut it off again.

 

I feel the AFM switch from V4 to V8 every time it does it. Also, I'd imagine it's because of AFM, but my truck has kind of a rough idle and smells like it runs rich! WTF? I'm just happy she's still under warranty for another 3 years...

KARNUT Senior Enthusiast

KARNUT

Posted
Posted

I hate it, I bought a V8 to get a V8. They added internal equipment and external equipment for cylinder deactivation, more stuff to fail. Some people claim 2 miles more per gallon with it, I didn’t see it. The took one of the most reliable engines out there and increased the odds of failure. I quit buying their cars after they stopped the rear drive sedan, no new GM trucks for me. Long live my 92!


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