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V4 mode

Gagliano7

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Gagliano7 Enthusiast

Gagliano7

Posted
Posted

I was driving my truck the other day and it started acting a little weird(trans on downshift) when coming to  a stop. I realized i hit my range with my knee and it wasn't plugged in. My trans shifts perfect all the time in V8 mode but V4 mode makes it act weird. I wonder what is in the tuning that makes act weird in V4 mode? Once my warranty is up i will have it programmed out but i wish V4 mode was option you could decline. And where i live with no flat roads anywhere V4 mode actually gets worse mpg in my truck.

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Jacoby Enthusiast

Jacoby

Posted
Posted

You’re truck shouldn’t be shifting in V4 mode. V4 is super sensitive and any time there is the slightest throttle input it will kick into V8. 

Donstar Senior Enthusiast

Donstar

Posted
Posted

If you're noticing V4 operation in your new truck without looking at the DIC then take your truck in for warranty work.   It is designed to operate seamlessly.  Many on this forum believe this feature to be problematic but I've logged a couple hundred thousand problem free miles with this technology.  I enjoy watching my current V6 switching in and out of V4 mode. ( I often wonder how often or if  my truck would ever switch to V8 mode if this was a feature!)

SS502 Senior Enthusiast

SS502

Posted
Posted
On ‎2‎/‎11‎/‎2019 at 9:45 PM, SS502 said:

Ehhh I don’t know but I only seriously started thinking about the Range after my service manager told me one of the reasons he decided to buy a Titan because they don’t have AFM. Lee Buick/GMC owns the Nissan dealership too and he’s been there for a while. We were talking about the transmission shudder problems and the new fluid. He said some people mistakenly thought they were having transmission issues when it was the V8 to V4 transitions. I never “felt” mine but certainly heard it.

 

1 hour ago, Gagliano7 said:

I was driving my truck the other day and it started acting a little weird(trans on downshift) when coming to  a stop. I realized i hit my range with my knee and it wasn't plugged in. My trans shifts perfect all the time in V8 mode but V4 mode makes it act weird. I wonder what is in the tuning that makes act weird in V4 mode? Once my warranty is up i will have it programmed out but i wish V4 mode was option you could decline. And where i live with no flat roads anywhere V4 mode actually gets worse mpg in my truck.

Maybe??

SS502 Senior Enthusiast

SS502

Posted
Posted
16 minutes ago, Donstar said:

If you're noticing V4 operation in your new truck without looking at the DIC then take your truck in for warranty work.   It is designed to operate seamlessly.  Many on this forum believe this feature to be problematic but I've logged a couple hundred thousand problem free miles with this technology.  I enjoy watching my current V6 switching in and out of V4 mode. ( I often wonder how often or if  my truck would ever switch to V8 mode if this was a feature!)

I agree to a point on this and this is only a guess...Maybe the transition from V6 to V4 isn't felt or heard as much as going from V8 to V4? you're losing 1/3 of your power plant where those with a V8 are dropping 1/2 of theirs. Don't know I've not driven the V6 just a WAG. 

Gagliano7 Enthusiast

Gagliano7

Posted
  • Author
Posted
54 minutes ago, Jacoby said:

You’re truck shouldn’t be shifting in V4 mode. V4 is super sensitive and any time there is the slightest throttle input it will kick into V8. 

It is when i am slowing down no throttle input and downshifting from 2nd to 1st. It never does this when my range is connected. I have had the range on since i had 20 miles on truck( only 3000 miles on truck now) and the only other time my range was disconnected was inspection time and it did the same thing then. I have a 2018 6.2. 

njk4o5 Enthusiast

njk4o5

Posted
Posted

love how people in other threads have been saying the 2016+ trucks dont have the problems of the past. same old shitty GM trans tuning

 

OP - take your truck in for warranty and battle them until they fix the rough downshifting. i brought mine to them 6 or 8 times until i got a new trans

mookdoc6 Senior Enthusiast

mookdoc6

Posted
Posted

I can climb long slow grades in V4 even with passengers...I would like to be in 4cly even more on the hwy?  Works good...can I sense it sometimes?  Yes, just don't care or not as tuned in as I was when it was new.  78K no problems DFM is probably really slick!

Donstar Senior Enthusiast

Donstar

Posted
Posted
2 hours ago, DeePa said:

You can definitely feel v8 to v4 if you have any clue about vehicles. 

The great advantage of belonging to a forum like this is learning from others.  I believe I have acquired a clue about vehicles and would like to benefit from your expertise.  The green indicator light tells me when I'm in V4 mode.  I can often predict when I can expect to see the green light but have no other obvious indicators.  There definitely isn't delay or hesitation when I accelerate while in V4.  Do you experience hesitation or a loss in speed?  I've had AFM since '09 and if it wasn't for the green light I wouldn't notice the difference.  If I did, I would take advantage of my powertrain warranty and get it repaired.  

ducklawyer Enthusiast

ducklawyer

Posted
Posted

My 14 was noticeable only bc of the chirp sound it made when switching (later identified as the flapper valve). Very seamless in my current 18. You should take it in.


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M1ck3y Senior Enthusiast

M1ck3y

Posted
Posted
7 hours ago, Jacoby said:

You’re truck shouldn’t be shifting in V4 mode. V4 is super sensitive and any time there is the slightest throttle input it will kick into V8. 

Not on the 6.2. GM actually states that because of the larger displacement over the 5.3 it can stay in afm longer because it can handle a higher torque load. And I can attest to this. Just last night it was driving me nuts, basically had to take it over 1/2 throttle to get out of chopper mode. I go through phases where I drive in m7 most of the time and then when fuel goes up I put up with the v4.

Gagliano7 Enthusiast

Gagliano7

Posted
  • Author
Posted
19 hours ago, njk4o5 said:

love how people in other threads have been saying the 2016+ trucks dont have the problems of the past. same old shitty GM trans tuning

 

OP - take your truck in for warranty and battle them until they fix the rough downshifting. i brought mine to them 6 or 8 times until i got a new trans

I don't think it is the trans. Trans shifts perfect with Range connected. The only time it has problems is when AFM is enabled. I don't really care much since it is a lease and i will turn it in when my lease is up.

TXGREEK Senior Enthusiast

TXGREEK

Posted
Posted

A couple days ago, I turned the AFM back on my truck through the SuperChips programmer and instantly noticed my transmission clunking and feeling shifts starting acceleration, turned it back off and next morning all good. Apparently, the AFM has something to do with the shifting of the transmission. I’ve had the AFM GM vehicles since 2007, never ever having issues with anything but now this does peak my (cautious) interests and will definitely keep an eye on it and servicing it as needed. One thing is for certain, very happy I’ve got the extended 100K warranty, hoping I won’t need it.


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