V4 mode problem ?
10-07-2018, 01:13 AM
#1
V4 mode problem ?
I have a 2016 z51 and the V4 have been annoying to me. i feel the vibration whenever v8 switch to v4. Sometime i crusing on highway and it keep vibrate every 30s. is it normal or something wrong ?
10-07-2018, 01:33 AM
#2
Drifting
My 2017 GS (M7) has a slight shudder when it drops into V4 but none going back to V8. Others have the opposite and some don't feel either transition. There doesn't seem to be any standard.
The first C7 I rode in, a 2014 Automatic, seemed to transition in and out of V4 fairly frequently on what seemed to be fairly flat roads. My GS doesn't switch nearly as often as that. I don't now if there have been changes to the programing for it or it is, again, different from motor to motor.
The first C7 I rode in, a 2014 Automatic, seemed to transition in and out of V4 fairly frequently on what seemed to be fairly flat roads. My GS doesn't switch nearly as often as that. I don't now if there have been changes to the programing for it or it is, again, different from motor to motor.
10-07-2018, 02:10 AM
#3
E-Ray, 3LZ, ZER, LIFT
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^^^
It’s been reported a “slush box” does not have a significant issue switching. Understandable as they can set a number of things like clutch pressures, torque converter, etc to do whatever is needed to make it smooth.
The few times I tired ECO in my 2014 C7 M7 could feel the transition on a flat intestate in 7th. A very slight hill on cruise control was enough to have it switch back to V8. Also understandable as the efficient, direct coupled clutch and engaged spur gears made a solid connection from engine to wheels.
Been 18 months with my M7 Grand Sport and have not used ECO mode yet, and no plan to do so. Have no idea what it feels like as ECO is the only drive mode it can engage.
It’s been reported a “slush box” does not have a significant issue switching. Understandable as they can set a number of things like clutch pressures, torque converter, etc to do whatever is needed to make it smooth.
The few times I tired ECO in my 2014 C7 M7 could feel the transition on a flat intestate in 7th. A very slight hill on cruise control was enough to have it switch back to V8. Also understandable as the efficient, direct coupled clutch and engaged spur gears made a solid connection from engine to wheels.
Been 18 months with my M7 Grand Sport and have not used ECO mode yet, and no plan to do so. Have no idea what it feels like as ECO is the only drive mode it can engage.
Last edited by JerryU; 10-07-2018 at 02:18 AM.
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Woodson (11-03-2018)
10-07-2018, 02:31 AM
#5
This may help. It has been viewed 14,796 times. Except for removing the AFM from the ZR1 motor, GM just fixes it one reported problem at a time, for free, until the warranty runs out. And maybe free later if a Class Action suit is ever filed against GM. I agree with above that the RANGE AFM disabler fixes this problem, best $189 option ever made for the C7, the Silverado and the Cadillac with AFM systems.
Shake or Shudder during light throttle acceleration TSB
Shake or Shudder during light throttle acceleration TSB
Last edited by SilverGhost; 10-07-2018 at 02:37 AM.
10-07-2018, 03:02 AM
#6
Le Mans Master
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Sorry to hear this. It needs the newer light weight transmission fluid, or a torque converter replacement. It is not normal to feel a shudder or feel the car in transition from V8 to V4 and vice versa. The Range device is not a fix, but could provide a band aid.
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10-07-2018, 02:25 PM
#8
Le Mans Master
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Disclaimer: The Range stopped the shudders for awhile in mine, but as the miles built up the shudder started coming through. I will now run the Range 100% of the time to keep the car out of that danged V4 mode, and in hopes it will help the TC in the process.
If you feel your dealer isn't the brightest bulb in the box, print out a copy of the TSB that SilverGhost posted. It should help you.
Last edited by Rebel Yell; 10-07-2018 at 02:31 PM.
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10-07-2018, 02:42 PM
#10
Le Mans Master
10-07-2018, 02:46 PM
#11
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St. Jude Donor '15-'16,'18
Welcome to the A8 Torque Converter Failure Club. Take it in and reference the TSB for shuddering. They will probably flush and refill your tranny and ask you to drive several hundred miles to see if this stops the shudder. If not, you will need a new torque converter. Good luck.
10-07-2018, 05:40 PM
#12
Drifting
I have a 15 with M7 trans keep in tour or sport mode never switches to V4 mode 
10-15-2018, 03:44 AM
#13
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St. Jude Donor '12
V4 mode? To heck with that. If its an a8 trans put the dam thing in M and paddle shift it. You will never see v4. If the car is an m7 trans the engine only goes into v4 if you put it in eco mode. Eco mode in a corvette? Are you kidding me! No eco mode in my corvettes!
10-17-2018, 08:58 PM
#15
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As far as I'm concerned ECO mode is not for drivers. It's for GM to save its CAFE bacon. Of course, that's easy for me to say since I have an M7.
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10-18-2018, 12:27 PM
#16
Le Mans Master
I have an M7 and have played with ECO mode out of curiosity. While not significant, I can feel it when it goes to V4 mode.
10-18-2018, 01:50 PM
#17
Racer
Take it to the dealer and tell them the transmission is shuddering. There is a TSB for this.16-NA-175
Be prepared for them to just do a flush and fill and hope that fixes the problem.
That is where I'm at right now. After a couple hundred miles, all seems fine.
There is also a document PIP5337E that suggests replacing the torque converter, but it's dated earlier than the TSB.
My transmission shifts way better now since they did the flush and fill. Whatever the new fluid is that they use, it made a big difference.
Be prepared for them to just do a flush and fill and hope that fixes the problem.
That is where I'm at right now. After a couple hundred miles, all seems fine.
There is also a document PIP5337E that suggests replacing the torque converter, but it's dated earlier than the TSB.
My transmission shifts way better now since they did the flush and fill. Whatever the new fluid is that they use, it made a big difference.
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Nghia Vu (11-02-2018)
10-18-2018, 07:18 PM
#18
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St. Jude Donor '15-'16,'18
Same result in my car after the flush and fill. I hope as the weather gets colder the shifting will remain smooth and no shudder.
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Nghia Vu (11-02-2018)
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Nghia Vu (11-02-2018)
11-02-2018, 11:37 PM
#20
Thank everyone for the advice. I will be bring her to the dealership asap. It's my first Corvette and it's not a garage queen! i drove it everywhere and i love everything about it. But this problem is SUCK! it's killing my mood.