Maxie2U

How many A8 owners plan to have fluid exchange procedure done regardless whether you have the shudder or as a preventative measure?

Many if not all have read GM released a TSB (TSB NA-18-355) in conjunction with a new ATF fluid (Quart P/N 19417577 with the blue banner across the label and license #J-62120 on the back) to address the torque converter clutch (TCC) shudder conditions on the 8L90 8-speed automatic transmissions.

My question is how many plan to have TSB NA-18-355 done regardless whether it’s covered under warranty or you have to pay out of pocket.

Flame Red

I did the "black label" fluid exchange myself back in November of last year before this new Wonder Fluid was announced. I just ordered a 6 pack of the magic blue label stuff from Summit and it should come this week. I'll use the same procedure as last time https://www.corvetteforum.com/forums/c7-tech-performance/4204078-how-to-tranny-flush-with-mobil-1-synthetic-lv-atf-hp-without-dropping-the-pan.html

I figure I need to get-r-done before the Florida Inferno starts again. Seems like it is selling out quickly - one day it was available from Summit and the next it was 6 week back order

STiRob

Does anyone know when the new fluid started being used at the factory?

orca1946

I will have this done at my next free oil change.

paki

I got the “could not replicate customer concern” when I took it in.

Keefer07

I had it done on my 2015. They covered it under my powertrain warranty. I wasn't expecting to notice any difference since mine had not started shuddering yet. It shifts much smoother now and I cannot feel it switch between V4 and V8 mode even when I watch it switch on the gauge.

Formula52

If I have to pay for this fluid change, how much $ do you think it will cost?

Thanks

DSPC7

On another forum under title Had New TSB #18-NA-355 (A8 Shudder) Done - the Cost was $625 not as a warranty service

Kevin A Jones

Does anyone have a copy of TSB NA-18-355 they could post?

DSPC7

Found on another thread

Srevice part 1
https://www.corvetteforum.com/forums...355-part-1.pdf

Srevice part 2
https://www.corvetteforum.com/forums...355-part-2.pdf

SgtMajUSMC(Ret)

I also posted it on this forum with invoice, here:

https://www.corvetteforum.com/forums...post1598909413

Keep in mind that does not include total tax and hazmat disposal fee of $110 split between the TSB and diff fluid change I had done at the same time.

MA ZO6

Here is some information (see attachment below) about the new fluid.I had it done to my car and it solved the shudder problem. It was covered under warranty as the need to hook up a device and make sure your car has the problem BEFORE they will cover it. If the device does NOT detect the shudder the fluid change will not be covered under warranty.

John

Patman

I have a late production 2018 (built the first week of Dec 2017) and have 9700 shudder free miles on my car, so I don't plan on messing with a good thing so I won't be changing the fluid until it's first regular service (maybe around 50 to 60k?).

thompstl1

It would appear my 2018 does NOT have the latest transmission fluid, is that your understanding from reading the information as well?

If so, I'd have no problem paying for the fluid change, finding a dealer that knows what they're doing and how to do it is the real challenge.

bankers1

16,000 Miles '17 GSCE # 663 A8 No problems so far. Produced 1/2017 It is really babied...

RichieRichZ06

You might.... The actual severity of the shudder must be logged and a snap shot taken to submit to GM. They know that everyone reads the forums and will be flocking to dealers for free fluid changes so there is a level of shudder that's considered normal and anything above that threshold can have the bulletin performed. Out of the 15 or so cars we've had come in over the last month, less than half were above the limit.

05XLRtoC7_San Diego

Hmmm....I have Range, so no shudder.
However, might be a good idea to have the fluid change performed at 50k instead of the usual 100k interval.

Interesting to hear this was covered under the 5 year transmission warranty on some cases even without shuddering?

RichieRichZ06

The stipulation for us confirming the shudder is above a certain level and recording that measurement is what changed. We've done dozens and dozens of them where we could confirm there was shudder, but there was no threshold that had to be exceeded so the fluid was changed.

LanceVette

Just got back from the dealer and they said my Corvette is not affected by this TSB. It's an early 2015 with the A8. I have not had any problems as of yet. Should I investigate further?

Keefer07

Dealer did mine under the powertrain warranty for peace of mind. I had no issues yet.