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Cylinder Deactivation Issues?

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Newell33 Enthusiast

Newell33

Posted
Posted (edited)

Some say they notice it, and some say they don't. I believe that some trucks behave differently than others, and I also believe some people are considerably more in tune with their vehicles than others. My '14 was horrible, especially when combined with the clunking, hesitating, flair shifting transmission. It drove me back to a '13 2500HD as soon as it financially made sense. I won't purchase another new truck with any kind of cylinder deactivation.

 

Edit: By the way, when I shut off AFM both with the Range device my mileage was exactly the same. Ultimately when I shut if off with a tuner, my mileage increased by 1 mpg.

Edited by Newell33
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pickmeup
pickmeup

One simple button with a choice . Economy or Sport mode . I believe it would have saved many many complaints .

j-ten-ner
j-ten-ner

You're not the only one. Because it's easier to turn of AFM than adding two cylinders.   so long j-ten-ner

Grumpy Bear
Grumpy Bear

Well I can see the difference right away. I don't have much flat ground and around here, Chicago area big wind is life. That said. Being on and staying on is quite something else. Yea, it turns on but

sk Senior Enthusiast

sk

Posted
Posted

I may be in the minority but I LOVE my AFM. It's one of the reasons I bought the truck. It definitely improves fuel mileage and I don't notice it switching in and out. I do a lot of highway driving and once I get up to around 55-65 and am just cruising along it switches to V4. But it's nice to know I have the V8 available as soon as I need it (and I use that mode often too)!

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Pearl2017 Enthusiast

Pearl2017

Posted
Posted

If AFM allows GM to claim .1 MPG and keep producing my beloved V8 I'm not against it. As long as its still modifiable feature to those that choose not to have it. AFM off = Wonky shifting gone.

Grumpy Bear Senior Enthusiast

Grumpy Bear

Posted
Posted

I'm more than good with the AFM in my 2015 1500. No switching issues. No oil usage. No blues. Smooth as a kitten. Just clicked over 19K on the clock. 5993 miles, 240.677 gallons = 24.90 MPG. What's not to like? :driving:

  • Like 1
JacobC1983 Enthusiast

JacobC1983

Posted
Posted

I hated it. I could feel the surges at low speeds from the torque converter locking and unlocking with the transition from v4-v8. Got a range and the truck is MUCH more enjoyable to drive.

  • Like 1
j-ten-ner Senior Enthusiast

j-ten-ner

Posted
Posted

... I am probably the only one these forums who is 100% happy GM is using AFM and not 6cyl turbo@! ...

 

You're not the only one.

Because it's easier to turn of AFM than adding two cylinders.

 

so long

j-ten-ner

  • Like 3
Donstar Senior Enthusiast

Donstar

Posted
Posted

I hated it. I could feel the surges at low speeds from the torque converter locking and unlocking with the transition from v4-v8. Got a range and the truck is MUCH more enjoyable to drive.

Did you take your truck in under warranty for service when it was having these problems? The transition from V4 - V8 is designed to be seamless. This was the case with my previous V8 and is with my current V6. If you did take it for service I am curious as to what the service adviser said about this issue.

JacobC1983 Enthusiast

JacobC1983

Posted
Posted

Did you take your truck in under warranty for service when it was having these problems? The transition from V4 - V8 is designed to be seamless. This was the case with my previous V8 and is with my current V6. If you did take it for service I am curious as to what the service adviser said about this issue.

Nope. Following the AFM thread, I am not the only one with these issues.

Donstar Senior Enthusiast

Donstar

Posted
Posted (edited)

Nope. Following the AFM thread, I am not the only one with these issues.

Do I understand this to mean that you didn't get the problem fixed or have I misunderstood? I believe that this feature is designed to work seamlessly. I did a 125km return trip on the highway today and tried to determine when my truck was switching in and out of V4 mode. I could not do it without looking at the DIC. I would be sure to mention this issue to your service adviser while your vehicle is still under warranty. No need to put up with faulty components when under warranty!

Edited by Donstar
JacobC1983 Enthusiast

JacobC1983

Posted
Posted (edited)

Taken from the AFM thread, fits my feelings perfectly and I have had a 2015 Sierra and 2016 Sierra while test driving at least 10 others...

 

"I think the debate regarding feeling the V4 is somewhat truck dependent and somewhat user feel. I think some trucks' V4 switching is a bit smoother than others. But I think some people are also more in tune with the changes that take place when the truck changes to V4...from the change in engine sound, the subtle back pressure that happens when it goes into V4, the change in the exhaust note, etc. I bet more often than not I can tell on any of your trucks when it's going into V4 mode without looking at the indicator on the dash. Sometimes it's hard to detect but most of the time I feel it and I also feel it way more in this truck than I ever did in my 2007."

Edited by JacobC1983
JacobC1983 Enthusiast

JacobC1983

Posted
Posted

Do I understand this to mean that you didn't get the problem fixed or have I misunderstood? I believe that this feature is designed to work seamlessly. I did a 125km return trip on the highway today and tried to determine when my truck was switching in and out of V4 mode. I could not do it without looking at the DIC. I would be sure to mention this issue to your service adviser while your vehicle is still under warranty. No need to put up with faulty components when under warranty!

 

No offense... but I bet I feel it on your truck too.

  • Like 1
Donstar Senior Enthusiast

Donstar

Posted
Posted

 

No offense... but I bet I feel it on your truck too.

Definitely no offence taken. If you could feel it on my truck and it demonstrates the same "surge" feel that you hate, I would be questioning you and not the truck! (lol) I don't doubt that your truck or others may have a faulty component. My point is for you to get it fixed if it is broken. Shortly after buying my truck, my front left signal light quit working. I didn't blame GM or hate my truck, I got it fixed. If you Google "left signal light not working" you get over 3 million hits. It is easy to find others that share a complaint. I doubt that you'd have a concern for this feature if it was working as intended!

Steve52 New Member

Steve52

Posted
Posted

I have a '14 Sierra with the 5.3 & 25K miles. I check my oil regularly and haven't noticed any oil use at all.

Gotta say I'm very pleased with the overall performance of this engine.

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