[T32803]

Background:

I bought a 2017 A8 V6 last Oct that definitely had the shudder problem.
I had the 2017 for 6 months then traded it an identical 2018 A8 V6
because the 2017 had paint issues. The new one came off the assembly
line mid Feb 2018 and I took delivery it in March.

My 2018 has only 600 miles now and I felt the shudder last weekend.

Believe it or not I thought the shudder problem was normal until now.
I thought the A8 was just too aggressive about keeping a high gear
loaded for maximum EPA ratings. I frequently curse that I wish the
A8 would downshift quicker to avoid all the laboring, vibration, and
what maybe felt like slippage.

It happens mostly when cruising 25-30 mph in city traffic then give it
some light acceleration. I get the rumble, vibration, and what feels like
the car is slipping in and out of gear. Maybe someone can help me
understand this but it almost feels like it is in a higher gear, then slips
out of that gear into no man's land for split second, then immediately
goes back into that same high gear to try again. The sound it makes
is like very low tone resonating hum.. Not a pleasant sound and
not a sound I've heard in any of the dozen or so cars I've owned.
The 2017 felt and sounded the same when this happened.

Also, when the car is in this shudder mode, the only way I can pull
it out of this funk is to hit the downshift paddle once or twice *OR* if
there if no traffic I can floor the gas. There's no other way right ?

I drove my previous G35 auto 135,000 miles never had a single
transmission issue or repair so I doubt this is a driver issue.

[chevyboy01438]

Picked my '17 SS up last night from the dealer regarding the shudder. The printed off a bulletin from GM that states it is an acceptable condition that has no impair to the performance of the car. Action was to do nothing. I told the guy I wanted to take out one of their new Camaros and see if it had the same issue but he wouldn't. I'm just glad I got the 6 year extended warranty incase something does happen

[Captain J]

Originally Posted by chevyboy01438

Picked my '17 SS up last night from the dealer regarding the shudder. The printed off a bulletin from GM that states it is an acceptable condition that has no impair to the performance of the car. Action was to do nothing. I told the guy I wanted to take out one of their new Camaros and see if it had the same issue but he wouldn't. I'm just glad I got the 6 year extended warranty incase something does happen

Where did they get that print out? I call BS on your dealer. Everyone is talking about the shudder and a TSB. The dealers are changing trans fluid and/or the TC.
I suggest you print out the TSB and go to a different dealer. It's TSB #16-NA-175

[T32803]

Originally Posted by Captain J

Where did they get that print out? I call BS on your dealer. Everyone is talking about the shudder and a TSB. The dealers are changing trans fluid and/or the TC.
I suggest you print out the TSB and go to a different dealer. It's TSB #16-NA-175

I agree, this sounds like total BS from the dealer. Please scan the "GM bulletin" and post it here so we see wrap our heads around this new twist. The A8 transmission is flawed and if I had understood the issues before now I would have passed on buying.

[01pewterz28]

I do not have the issue on my 17 SS but I printed a copy of the TSB and keep it in the glove box just in case I need to use it.

[zx9rmal]

www.revbase.com/BBBMotor/TSb/DownloadPdf?id=201234

[KMPrenger]

Everyone should take a look at the "Ask Al" section on this website. This issue was brought up and actually received a response from Al.

https://www.camaro6.com/forums/showthread.php?t=527133

Doesn't seem to help in this case though.

[Nsxmatt]

I have a 17 V6 which was in the build date to not have any problems but in the first 1000 miles I would feel it occasionally around the 20-30mph range. Once it got to about 2000 miles it went away completely and I haven't felt it since.

I'd drive it for a while and see if it gets worse or goes away. If it's a problem it will get worse and warranty will cover it.

[JT58]

I had varying RPM's and slippage- the RPM would fluctuate when driving a steady speed, then I had the shudder happen also one time. I immediately brought in to the dealer- they knew all about it and did the tranny flush. So far no more issues.

[modru2004]

what hes describing sounds more like AFM than the transmission shudder other people have experienced.

[T32803]

Originally Posted by modru2004

what hes describing sounds more like AFM than the transmission shudder other people have experienced.

If this is the case, it should be a 1 or 2 second thing and return to normal.
This is not what happens. The car remains in this state of running rough and
car feels very slightly jerky in it's movement until I floor the gas or hit the
manual down shift twice. When it happened last weekend I did not see the
V4 light on either.

[modru2004]

Originally Posted by T32803

If this is the case, it should be a 1 or 2 second thing and return to normal.
This is not what happens. The car remains in this state of running rough and
car feels very slightly jerky in it's movement until I floor the gas or hit the
manual down shift twice. When it happened last weekend I did not see the
V4 light on either.

so when its in this state what happens when you flick it to manual mode. (NOT hitting the paddles, just flicking the console shifter over to M). not changing gears just a simple switch to manual mode. make note of the gear and any behavior changes.

after that i would try driving in manual mode and select the gear you noted above and try and replicate similar driving circumstances to try and replicate the issue.

[T32803]

The Shudder bulletin describes the condition as this:

• A shake and/or shudder during light throttle acceleration between 40 and 128 km/h (25 and
80 mph) steady state driving when transmission is not actively shifting gears.
• A shudder feeling that may be described as driving over rumble strips or rough pavement.
• Shudder feeling is evident in both Drive and M7 MY15-16 & L7 MY17 mode.

This is exactly what I hear and feel. Especially the sound and vibration as if I
was "driving over rumble strips or rough pavement".

It only occurs (that I notice) during light throttle acceleration between 25 and 50 mph
usually after I have been cruising in traffic then try to add a little bit of speed. I virtually
never see the green V4 light come on because I am always driving in the city.

What is it about my description that makes you so sure that it is AFM and not shudder?

If I am not seeing the green V4 light come on then how can it be AFM?

And if AFM can be a problem even when the V6 light is always on, then how the heck can
it last for long periods of time unless I intervene and force it with a manual downshift
or flooring it ?

[crosive]

If you throw it into manual mode, and sport, and downshift, it should remove afm from the equation until you change modes back. When mine was exhibiting the problem, it did it in either mode, but v4 mode was accentuated worse.