Active Fuel Management

jimturn1 · November 20, 2014

Drive a 2014 Sierra with a V6, I notice a slight flutter/shudder at times while at all speeds and especially noticed when I let up off the accelerator than accelerate again. The dealer states that I am felling the effects of the active fuel management system. I thought my problem was in the transmission? Any suggestions on this!!

KARNUT · November 20, 2014

Drive a 2014 Sierra with a V6, I notice a slight flutter/shudder at times while at all speeds and especially noticed when I let up off the accelerator than accelerate again. The dealer states that I am felling the effects of the active fuel management system. I thought my problem was in the transmission? Any suggestions on this!!

Its a little of both. When your under 60 put your truck in M5 and it will smooth it out some. When you go over 60 click up to 6 and the V4 will kick in again. These trucks process a lot, little hitches are to be expected.

GMCustomerService · November 20, 2014

Hey Jim,

We see you're concerned about a shudder when you're accelerating in your 2014 Sierra. We'd be happy to reach out to your dealer for clarification and look into this further for you. Please feel free to send us a private message if you're interested. If you're unable to send private messages at this time, we can also be reached via email at [email protected].

Sincerely,

Eddie A.

GM Customer Care

pm26 · November 20, 2014

N-o-r-m-a-l !!!!!!!!!

scott19677 · November 21, 2014

First gear = shudder, Second gear =shudder, Third gear= feels fine. I don't know if its the trans, or tq management but all three of my 2014s do this. I would like to hear from someone if this could be fixed with a tune. It just doesn't FEEL right.

AGEURTS32010 · November 21, 2014

First gear = shudder, Second gear =shudder, Third gear= feels fine. I don't know if its the trans, or tq management but all three of my 2014s do this. I would like to hear from someone if this could be fixed with a tune. It just doesn't FEEL right.

I agree!

jimturn1 · November 22, 2014

Should the AFM system work at all speeds, noticed that it will engage at lower speeds?

20L8TSierra24 · November 22, 2014

I hate how on a slow acceleration it switches to v4... Sounds and feels like crap...

2016 Sierra Owner · November 22, 2014

Should the AFM system work at all speeds, noticed that it will engage at lower speeds?

Yes it will work at low speeds. Just cruising around the neighborhood it will stay in V4 for me. 15-25 mph.

Isriam · November 23, 2014

get a custom tune, your truck will feel like a corvette compared to stock.

2017SierraSLT · November 26, 2014

AFM sucks, even in the new trucks. Tune it out, and feel the refinement!

tbare54 · November 26, 2014

Mine was doing the same thing, I see all kind of complaints in different threads, for what sounds to be the same problem. There is a service bulletin for the EXHAUST FLAPPER VALVE, which addresses the problem, mine was done about 3 months ago, basically they replace the exhaust system, from the catalytic converter back. Since having mine done it definitely sounds and runs better, I think my fuel mileage may have improved a little bit. Don't know if the problem will come back, but I'm betting a big percentage of these trucks with V8 or V6 are having this problem, everyone just needs to have the dealer check the exhaust flapper valve and replace the exhaust system.

jimturn1 · November 27, 2014

get a custom tune, your truck will feel like a corvette compared to stock.

what is a custom tune?

MudMutt · November 27, 2014

Its a little of both. When your under 60 put your truck in M5 and it will smooth it out some. When you go over 60 click up to 6 and the V4 will kick in again. These trucks process a lot, little hitches are to be expected.

I totally agree ... City driving use M4 or M5 ... Get on the highway and use the AFM. I had a 2012 Doge Ram Bighorn that I traded for the Silverado. The truck shuttered badly at low speeds when the AFM kicked in. With the Dodge you felt it in the steering column. I had the floor shifter with the built in paddle .... Just kept it in 5 in the city ... No AFM ... Smooth as silk. AFM is getting better but still not there yet IMO.