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Active Fuel Management vs Dynamic Fuel Management Infographic

Zane

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No Coast Rider Enthusiast

No Coast Rider

Posted
Posted

I put a Range in my 15 5.3 2 months after buying it, truck rides so much better and my MPG actually improved by almost 1 MPG. I don't have an issue with the technology, I had a 2007 Dodge Magnum with the 5.7 HEMI with MDS and that system worked great, When you were cruising it would cut down to 4 cylinders and as soon as you started to press on the gas more it switched back to 8 and off you went. The GM system is awful, there's too much lag between when I press the gas and when it gives you back 8 cylinders and it makes acceleration very jerky, which is probably why so many people think the transmissions suck. Based on this chart, if I was buying a 2019 (Which I absolutely won't do, it looks awful,) I'd buy another LS with a basic 5.3 with AFM and put another Range in it, and as a bonus I don't have to worry about disabling start/stop every time I get in it either.

Loco Diablo Enthusiast

Loco Diablo

Posted
Posted
I put a Range in my 15 5.3 2 months after buying it, truck rides so much better and my MPG actually improved by almost 1 MPG. I don't have an issue with the technology, I had a 2007 Dodge Magnum with the 5.7 HEMI with MDS and that system worked great, When you were cruising it would cut down to 4 cylinders and as soon as you started to press on the gas more it switched back to 8 and off you went. The GM system is awful, there's too much lag between when I press the gas and when it gives you back 8 cylinders and it makes acceleration very jerky, which is probably why so many people think the transmissions suck. Based on this chart, if I was buying a 2019 (Which I absolutely won't do, it looks awful,) I'd buy another LS with a basic 5.3 with AFM and put another Range in it, and as a bonus I don't have to worry about disabling start/stop every time I get in it either.

At 22k miles, my 2017 5.3 with AFM has been seamless. Unless you’re looking at the display, you can’t tell when it changes modes.


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Loco Diablo Enthusiast

Loco Diablo

Posted
Posted
I've heard of several with failing injectors right out of the gate, and this was several months back. All less than 3k miles, some less than 700 mi..
 
That's the joy of buying new - you don't really know how "great" a deal you got until you're well out of the warranty period.

I have at least 8 friends I can think of the newer model trucks (2015+). Not one has had AFM related issues. Knock on wood!


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No Coast Rider Enthusiast

No Coast Rider

Posted
Posted
7 hours ago, Loco Diablo said:


At 22k miles, my 2017 5.3 with AFM has been seamless. Unless you’re looking at the display, you can’t tell when it changes modes.


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My truck is an LS with the basic monochrome HUD so it doesn't display which mode the engine is in. I can tell by exhaust note (with stock exhaust) and by the performance when you hit the gas. there a really bad delay before it kicks back to 8.

  • 7 months later...
Ryan Trask New Member

Ryan Trask

Posted
Posted

I hate the AFM in my 2018 Silverado.  Dealership told me to put it in L then select 6 and it'll run v8 all the time.  Gas mileage obviously went down. But I'd rather that than the afm v4 to v8 switch

Wiggums Senior Enthusiast

Wiggums

Posted
Posted

I have DFM in my new 2019 Silverado 5.3 V-8 and I've noticed it lags a lot. I hit the gas and nothing happens for a second then comes the surge of power. Not sure if it's the DFM but it's likely.

ChevyTodd Enthusiast

ChevyTodd

Posted
Posted
35 minutes ago, Wiggums said:

I have DFM in my new 2019 Silverado 5.3 V-8 and I've noticed it lags a lot. I hit the gas and nothing happens for a second then comes the surge of power. Not sure if it's the DFM but it's likely.

That’s strange because I have absolutely no lag at all. If I hadn’t been told the engine has DFM, I’d never know.

Wiggums Senior Enthusiast

Wiggums

Posted
Posted
15 minutes ago, ChevyTodd said:

That’s strange because I have absolutely no lag at all. If I hadn’t been told the engine has DFM, I’d never know.

Not even from auto/stop? 

ChevyTodd Enthusiast

ChevyTodd

Posted
Posted
11 minutes ago, Wiggums said:

Not even from auto/stop? 

Not really. By the time I take my foot off the brake, it’s fired back up and hit the throttle and go. I thought I’d hate the auto/stop feature, and figured I’d be turning it off every time I got in the truck, but it’s really not an issue.

Smitty Enthusiast

Smitty

Posted
Posted

I can tell the auto start \ stop is happening but it's so quick it's not a hindrance at all.  By the time you go from brake  to gas it's ready.  I do think the DFM helps as well.     I could live without the auto start \ stop but i do enjoy the mileage i'm getting on a 2019 either way. 

Wiggums Senior Enthusiast

Wiggums

Posted
Posted
1 hour ago, ChevyTodd said:

Not really. By the time I take my foot off the brake, it’s fired back up and hit the throttle and go. I thought I’d hate the auto/stop feature, and figured I’d be turning it off every time I got in the truck, but it’s really not an issue.

 

Same here, had auto/stop off and the lag is really bad, as if it needs to gather its composure. That's why I think it's DCM. Really have no idea but will have that checked.

  • 2 weeks later...
wizard4878 Enthusiast

wizard4878

Posted
Posted
On 3/26/2019 at 3:45 PM, ChevyTodd said:

That’s strange because I have absolutely no lag at all. If I hadn’t been told the engine has DFM, I’d never know.

same here, I have no idea how many cylinders are active

  • 11 months later...
mike5511 Enthusiast

mike5511

Posted
Posted

I couldn't tell when it was on in my 2015 except by the light, and can't tell in my 2020 either.......and I wish there was a light in the 2020s. I do not have the Dynamic AFM.

 

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