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Hopefully sooner than later.
They did a recall update on my truck.  The description for the update said the valve could cause a check engine light that would disable the DFM until it was reset.
That means the DFM can be shut off with the right signal.
 
 
5c4647f345ea4_ScreenShot2019-01-21at5_24_48PM.thumb.jpg.21bce3d1e23eee32036910b0428f7a6f.jpg



Under certain conditions DFM will not run. It is not as simple as an on/off switch like AFM though. If it was the Range device would already work for it.

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Hopefully sooner than later.
They did a recall update on my truck.  The description for the update said the valve could cause a check engine light that would disable the DFM until it was reset.
That means the DFM can be shut off with the right signal.
 
 
5c4647f345ea4_ScreenShot2019-01-21at5_24_48PM.thumb.jpg.21bce3d1e23eee32036910b0428f7a6f.jpg



Under certain conditions DFM will not run. It is not as simple as an on/off switch like AFM though. If it was the Range device would already work for it.

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sure would be nice if we could get some sort of updates on the progress they are making.  Maybe my truck is different, but I can definitely tell when DFM is going.  It's the most noticeable at about 1200-1300 RPMs.  Kind of vibration feel.  Drives me crazy, and there's also a lag when your in that and punch the gas before it goes.  On my 15 Sierra I had a range and a sprint booster on the gas pedal, and that combo made night and day difference.  Hopefully when Range gets done and all 8 are firing all the time the lag will be eliminated for the most part.

 

Does anyone know what the certain conditions are that DFM won't run?  I wonder if it does in sport mode or tow

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I can't even notice the DFM unless I'm totally stopped and when you take your foot off of the break to apply the gas you feel \ hear everything kick back in.   Maybe I just need to get use to it but I have to think that's rough on the engine doing that start \ stop function constantly.   

 

I haven't done my research on DFM and how long it's been around but I'm hoping this doesn't cause any problems with engine etc long term.  I agree they have probably sunk millions into research and development and wouldn't have done it if it didn't make sense.  I'm just not use to driving a vehicle with it. 

 

Smitty

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On 2/22/2019 at 10:21 AM, Smitty said:

I can't even notice the DFM unless I'm totally stopped and when you take your foot off of the break to apply the gas you feel \ hear everything kick back in.   Maybe I just need to get use to it but I have to think that's rough on the engine doing that start \ stop function constantly.   

 

I haven't done my research on DFM and how long it's been around but I'm hoping this doesn't cause any problems with engine etc long term.  I agree they have probably sunk millions into research and development and wouldn't have done it if it didn't make sense.  I'm just not use to driving a vehicle with it. 

 

Smitty

That's the auto start/stop, not DFM.     

 

 

 

 

 

 

 

I have to say, I haven't noticed my DFM, makes me wonder if it's actually working. 

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That's the auto start/stop, not DFM.     
 
 
 
 
 
 
 
I have to say, I haven't noticed my DFM, makes me wonder if it's actually working. 

It’d be neat for them to add a screen that shows which/how many cylinders are running, cool little graphical display. Would be easy for them to do, although would probably never happen.
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5 minutes ago, FirstAscent said:


It’d be neat for them to add a screen that shows which/how many cylinders are running, cool little graphical display. Would be easy for them to do, although would probably never happen.

I believe AFM trucks have a 4cyl light.   I don't see what would have been difficult in just adding a DFM info screen with all the other things they have in there. Breakdown of how long the truck was running in each mode or just what mode its in. 

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On 1/21/2019 at 5:20 PM, AtlasFBG2 said:

Unless you get a LT or RST model with the 2.7L 4 cylinder. That engine uses AFM.

AFM on a 4 cylinder? What the heck happens? Does it drop to 2 or 3 cylinders???

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58 minutes ago, SS502 said:

AFM on a 4 cylinder? What the heck happens? Does it drop to 2 or 3 cylinders???

Yes the 2.7 4 cylinder drops down to 2 cylinders in afm mode.

 

The 5.3 and 6.2 engines that use dfm actually can drop down to 2 cylinders also.

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5 minutes ago, AtlasFBG2 said:

Yes the 2.7 4 cylinder drops down to 2 cylinders in afm mode.

 

The 5.3 and 6.2 engines that use dfm actually can drop down to 2 cylinders also.

5.3 and 6.2 in the 2019 I’m guessing? I have a 2018 and Range to keep AFM OFF. Oh I just saw DFM can do that to the 5.3 and 6.2.....that’s just wrong lol

Edited by SS502

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1 minute ago, SS502 said:

5.3 and 6.2 in the 2019 I’m guessing? I have a 2018 and Range to keep AFM OFF.

Yes on the 2019 trucks.

 

The WT,Custom and Custom trail boss use the 4.3L and 5.3L with AFM which drops down to 4 cylinders.

 

The LT, RST, LTZ, LT trail boss and High Country  use the 2.7L 4 cylinder with AFM, 5.3L and 6.2L with DFM. All three engines drop down to 2 cylinders. Actually the 5.3 and 6.2 can run on anything from 2 cylinders to 8 cylinders.

 

Video explaining the 4 cylinder if you got 10 minutes to watch.  https://www.bing.com/videos/search?q=2019+chevy+silverado+4+cylinder+turbo+afm&qpvt=2019+chevy+silverado+4+cylinder+turbo+afm&view=detail&mid=DC856F77C3777BDB05C1DC856F77C3777BDB05C1&&FORM=VRDGAR

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On 2/23/2019 at 12:45 PM, MadCaddie said:

That's the auto start/stop, not DFM.     

 

 

 

 

 

 

 

I have to say, I haven't noticed my DFM, makes me wonder if it's actually working. 

Well i hate the auto start/stop, that drives me crazy.   I don't want to have to turn it off each time i start the truck either!   

 

As far as the DFM portion, I can't tell if it drops down to fewer cylinders, if it does it's amazing.   I assumed the Auto start \ stop was actually the DFM because THAT is obvious.  hahha

 

Thanks for clarifying for me. 

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On 22/01/2019 at 11:52 AM, GMC-AT said:

It doesn't matter what people think.. it's hear to stay. Pretty much every new car & truck will have auto start / stop by next year.  I know Ford, Dodge already have it. So if you don't like it... keep your old Silverado forever, or buy the plug in hack that disables it.  

 

People also have to remember that there are a lot of truck buyers that aren't brand loyal.. they only care about MPG. So if GM or Ford, etc... can implement these little things and squeeze out an extra 1 mpg over their competitor.. they will sell more trucks just based on that. 

Unfortunately driveability suffers as all of us enthusiast know. I personally could care less about MPG.. but many people do...GM, Ford, Dodge, etc, understands this. 

 

 

I'm sure mileage isn't the only thing people will switch for. Capability (though probably more so in the heavy duties), price, drivability, etc. Not arguing with you, just saying you really need an all around good truck if people aren't going to be brand loyal. 

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I just currently talked to range and they said that their product will work with the trailboss that used AFM .. so the custom. I just placed an order with them today and should get it by the end of the week. I will do a follow up video to see how it does

Sent from my SM-N960U using Tapatalk

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I was all set to buy a range device mostly to keep all 8 cylinders firing however for the following reasons I have not:

 

1. I dont KNOW that cylinder deactivation will cause future problems and I really like the gas mileage. I have no issues with how it runs. 

2. I can turn off auto stop and do every time I start the truck.

3. Afraid of possible warranty coverage issues. 

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