[arpad_m]

Originally Posted by SkySerpent

*Update*

Did the test drive. I could feel the vibration in the passengers seat. Every time he was in V4 mode and accelerating it vibrated. He confirmed the vibration existed (which is an improvement from a month ago when they said it didn't exist). However he stated it was "normal" vibration from the transmission and every other Camaro he drove exhibited the same behavior.

I asked about the oscilloscope test and he responded with GM wont pay them to test it and the car doesn't warrant a test as this vibration is "normal".

My symptoms:
-Vibration 90% of the time when from V4 to V6 mode and lightly accelerating from speeds 40km/h to 130km/h (more common 80-130km/h)
-Some vibrations are accompanied by the tachometer fluctuating approx 100-200rpm up and down.
-Severe vibrations are accompanied with a loss of acceleration for a few seconds. I can put the pedal halfway down and get no acceleration, only vibration. These are rare (5 times in 2 months).
-ALL vibrations occur while in a single gear. Most common 7th and 8th. uncommon 4th, 5th, and 6th.

I'm not stupid enough to think these are "normal" but I also am not a transmission expert.

I've been to 2 dealerships and both said nothing is wrong and vibration is "normal".

If I contact Chevrolet Canada can they do anything?

You are not mistaken, this is the shudder, see links above to threads discussing it, and find attached the TSB to show the dealer.

I understand this is pretty frustrating, however, the new 2019 fluid and (if that isn't enough) a new torque converter fixed the issue for many, in fact I don't recall any verified reports of the shudder returning after that.

[ARCamaroGuy]

It is definitely the torque converter. Even after a flush of new fluid for the tranny, the tc can be damaged beyond something a flush can fix. It can be permanently damaged from the wrong fluid and need replacing along with a flush of new fluid. This is covered under your powertrain warranty. Might be time to find another dealership imo

[DannyC]

I have the A8 and the first time I drove it from Appomattox home I had it in cruise control and was driving 60 or less. I noticed the vibration a lot and was worried.

I did some research, bought a Diablo iTunes 3 and disabled AFM and the vibration reduced by 80%. The gears are so close together in the A8 it just shifts a lot. I usually switch to manual mode after I get up to my normal driving speed. No more constant shifting but you can still feel the TC on slower back roads.

[Jfowler81]

Mine is getting a new tc and some valves replaced in the transmission whenever the parts come in. I had a flush done today and it still had a chatter so the dealership ordered the parts.

[SkySerpent]

Called Chevrolet Canada, opened a ticket. Will know more by Monday what is going to happen. Will keep everyone up to date as this progresses. I am concerned about damage to my transmission. I will not void the warranty until I know everything is ok.

[SkySerpent]

*Update* Chevrolet will not repair the car as it was found all the vibrations I was having were deemed to be normal operational condition for the A8 transmission when in AFM mode. I asked for a oscilloscope test to put my mind at ease. They said one was already on record and had no issues. Problem is I have no record of anyone performing the oscilloscope test. GM really doesn't want to address my problem. I will be sending them a letter to complain.

[arpad_m]

Originally Posted by SkySerpent

*Update* Chevrolet will not repair the car as it was found all the vibrations I was having were deemed to be normal operational condition for the A8 transmission when in AFM mode. I asked for a oscilloscope test to put my mind at ease. They said one was already on record and had no issues. Problem is I have no record of anyone performing the oscilloscope test. GM really doesn't want to address my problem. I will be sending them a letter to complain.

Until then, you may want to consider a plug-and-play Range device that turns off AFM / V4 mode and is not going to affect your warranty.

[SkySerpent]

Originally Posted by arpad_m

Until then, you may want to consider a plug-and-play Range device that turns off AFM / V4 mode and is not going to affect your warranty.

Already have one. Although I'm almost 100% sure its just going to get worse. Even with the AFM disabled. Very disappointed in Chevy right now, but I guess if they fixed the TC they would be admitting something is actually wrong with it.

[Spartan268]

That sucks to hear. When I first got the shudder issue and got it fixed the service advisor tried to play it off as saying vibrations are normal in a sports car. He also said this might happen again, if it does it's nothing they can do. I argued with him for a good bit saying older sports cars from Chevy have been a lot more stable than this so you can't lie to my face. This is on top of the 120km they put on the car for "diagnostics" and the half tank of gas they burned. I never left a dealership so angry before and vowed to never go again. (Dueck on Marine)


Since then I switched to another one who handle a lot of Corvettes and they've been treating me better since. Thankfully my shudder issue has not come back yet. But when I got it fixed it was with the older fluid recommendation so I guess it's only a matter of time before it comes up again.


I'm guessing the Canadian side of GM sucks compared to their American side. It probably helps that we consumers have less power in Canada so they can say and do whatever they want. There's also an option of getting a TCM tune as well. Supposedly setting the slip values in the transmission tables to 0 will fix the issue assuming the damage has not been done yet to the TC.

[wwiiavfan]

Originally Posted by SkySerpent

*Update* Chevrolet will not repair the car as it was found all the vibrations I was having were deemed to be normal operational condition for the A8 transmission when in AFM mode. I asked for a oscilloscope test to put my mind at ease. They said one was already on record and had no issues. Problem is I have no record of anyone performing the oscilloscope test. GM really doesn't want to address my problem. I will be sending them a letter to complain.

Probably because they know the next step to fixing it is TC replacement, which is hecka lot more expensive for them than a flush.
Others on here can chime in, but I think the instances of TC replacement by GM is pretty small compared to multiple flushes, trying to kick the can farther down the road.
I guess all I can say is be persistent (without losing your cool) with them, or try a new dealer.

[SkySerpent]

Originally Posted by Spartan268

That sucks to hear. When I first got the shudder issue and got it fixed the service advisor tried to play it off as saying vibrations are normal in a sports car. He also said this might happen again, if it does it's nothing they can do. I argued with him for a good bit saying older sports cars from Chevy have been a lot more stable than this so you can't lie to my face. This is on top of the 120km they put on the car for "diagnostics" and the half tank of gas they burned. I never left a dealership so angry before and vowed to never go again. (Dueck on Marine)


Since then I switched to another one who handle a lot of Corvettes and they've been treating me better since. Thankfully my shudder issue has not come back yet. But when I got it fixed it was with the older fluid recommendation so I guess it's only a matter of time before it comes up again.


I'm guessing the Canadian side of GM sucks compared to their American side. It probably helps that we consumers have less power in Canada so they can say and do whatever they want. There's also an option of getting a TCM tune as well. Supposedly setting the slip values in the transmission tables to 0 will fix the issue assuming the damage has not been done yet to the TC.

Since I've had the fluid change procedure done and the vibration came back. I suspect damage has already occurred to my TC. I drive the car a lot more then most people on this sub.

For those interested. I have a video of the vibration. Video doesn't do it justice as it feels like I'm going over a rough patch. I will be trying to get the speedometer in the next video.

At 0.16s I gave her 3/4 of the gas pedal. She didn't move. You can see the camera vibrate and the sound of the car changes. I cut the video before I took off like a scalded cat..
https://youtu.be/ym1oIpdC6ks