DFM activated while driving.....

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Hi all,
Is there some indicator on the dash that turns on/off when DFM is activated/deactivated while driving?
THX
B
 
Hi all,
Is there some indicator on the dash that turns on/off when DFM is activated/deactivated while driving?
THX
B
If there is, I have not discovered it yet. I can feel when it’s active through the steering wheel (slight vibration). I have been driving in L9 or L8 since the first 400 miles, after I discovered that doing so disables the DFM altogether.

My 2017 model with the L86 engine and AFM had an indicator on the dash, but I think GM deleted that with the L87 engine.

The L86 engine could disable 4 cylinders, but the L87 engine can disable up to 7 cylinders (as I understand).
 
WHAT ABOUT THE START/STOP BUTTON? Doesn't that turn off the system? I always disable it (turn it off) when I start the engine.
 
If there is, I have not discovered it yet. I can feel when it’s active through the steering wheel (slight vibration). I have been driving in L9 or L8 since the first 400 miles, after I discovered that doing so disables the DFM altogether.

My 2017 model with the L86 engine and AFM had an indicator on the dash, but I think GM deleted that with the L87 engine.

The L86 engine could disable 4 cylinders, but the L87 engine can disable up to 7 cylinders (as I understand).
My Jeep has an indicator on the dash when the engine switches to 4 cylinder mode, was wondering on the truck.
 
I use my Banks gauge
I use my nose and watch the fuel mileage drop.

I tracked hundreds of them on my last rig over 10 years and when I was done, I wondered why the hell did I track hundreds of these over 10 years to prove it worked just fine time and again.

The emissions system is now the most reliable parts in these trucks....... go figure!
 
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I use my nose and watch the fuel mileage drop.

I tracked hundreds of them on my last rig over 10 years and when I was done, I wondered why the hell did I track hundreds of these over 10 years to prove it worked just fine time and again.

The emissions system is now the most reliable parts in these trucks....... go figure!
I have been through several regens now and have failed to see a fuel mileage drop during my regen. Maybe if I got my nose out of my @$$, I might have smelled something too :unsure:
 
I have been through several regens now and have failed to see a fuel mileage drop during my regen. Maybe if I got my nose out of my @$$, I might have smelled something too :unsure:
That's cause they get horrible mileage so it won't drop much. It's easier to see in older vehicles.

When your regening, you can see increased RPMs at idle, which is how they keep the heat in the DPF to burn off the soot. You can only usual smell it if your outside the vehicle. Also, if you think your regening, you can stomp the throttle and sometimes see whitish gray soot come out the exhaust. Easier to see in the dark when headlights are behind you.

This system seems to be pretty refined, so that's why I don't worry about tracking it. I do know it consumed a lot of DEF when towing.
 
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