pkincy

Thihs thread is not the most uptodate on the subject the new TSB, all 30 pages of it, is posted in 2 pdf files in another "Shudder" thread. But the permanent fix is a 3rd try at a new fluid and a new flush/fill procedure using new equipment for many of hte A8 equipped cars, although I think our Corvettes have gone back to the labor intensive triple flush with the new fluid. TSB 18-NA-355 is your search term after "shudder."

Prray

Hey Guys, I just got my 2017 Stingray with 6,000 miles on it back from the dealer on Friday after performing the triple flush with the new oil,trans pan cleaning and lines flushed out. So far I have only put 47 miles on it and it seems to be good, I have my fingers crossed and toes hopefully it will last so, will see. I was not told or saw nothing on the repair order that a new program was updated just the new flush procedure was done. I also have a friend that had his 2017 GS done 2-weeks ago at a different dealer and he has put about 300 miles on his and he stated no more shudder, crazy such an expensive car to be going threw such drama. It will be interesting what other fix will come out and also I'm sure you have all heard of the class action suit that is pending, wow!!

MidLife+

I also had the NEW 2019 triple fluid flush last week. I put on about 200 miles on it this weekend. All appears OK so far. I did reinstall the Range AMF disabler back on the ODB2 port before I drove off the service lot.

All the previous fixes over the last few months didn't work. I have had a fluid flush before they come up with the newest 2019 fluid, I also had the torque converter replaced and the transmission valve body replaced. All of these early fixes were not successful in removing the shudder. The valve body did help the harsh shifts (both up and down shifts).

For now it does appear that the shudder is gone! - TSB # 18-NA-355

Har-ray

rmorin1249

All of these "fixes" are bandaids. Post warranty repairs are going to cost a fortune to eliminate the shudder. GM should at least offer an extended warranty for 10 years or 100K miles.

dotbowels

wheres new TSB?

pkincy

Search for 18-NA-355. It is posted in 2 parts.

MA ZO6

See attached below, the end of part 2 has the Corvette instructions.

John

Red C8 of Jax

Had the shudder and the dealer used the NEW fluid flush; however, I noticed my shudder was back the next day. Does shift better. Will take car back to the dealer and see what their plan B is.

Eric Simon

Two weeks into the triple flush or just shy of 200 miles and until yesterday the vette had never shifted better. I guess hoping for the best I was tossed a little curve last night when putting a little pedal to the metal the transmission had a significant miss. I put another twenty miles on the car with no further problems. As this is the third in a series of transmission flushes over the past two years I’m now obviously concerned this too will deteriorate with additional miles and the Shudder will return. Keep you posted as the bulletin states a minimal of 200 miles must be put on the vehicle before Shudder is completely eliminated. “Keep You Posted”

1SG_Ret

The C8................

Har-ray

Had the permanent fix done in Jan. Shudder returned. Having 2nd triple flush “permanent fix” tomorrow. I hope this is a little more “permanent”.

SilverGhost

I just traded a 17 z51 at 5500 miles with no A8 issues. Trade in to a chevy dealer who detected no trans issues. At mile 3 off the showroom floor I used manual shift to ensure it never went Into v4 mode, until my range arrived. I just moved the range to a new Z06 which I hope will also never see v4 mode. The range cost $189 new, I keep the instrument display to the beautiful orange v8 display, never seeing the dreaded green meanie v4. Cheapest peace of mind i've ever purchased. But you don't even have to pay that, just use the a8 in manual mode to upshift, it down shifts automatically.

First tank after breaking in 22.0 mpg running 75-80 all interstate, well, some extra gotta pass long lines of slow pokers acceleration exercises too. The gauge said avg 25 mpg, the pump gallons to refill and trip odometer reading calculated 22mpg.

The hundreds of thousands of chevy's, gmcs, and Cadillac a8''s affected can't be ignored. BUT gut instinct tells me GM already fixed the a8 problem when they ELIMINATED Automatic Fuel Management AFM from the ZR1 engine.

CP

I still have the RPM variations even after the new tranny fluid triple flush. I think this is hopeless. Long live the Range.

kaplana08

You are right just a bandaid. The tranny is defective and a dud. GM hoping everyone will eventually go away. I would not touch the 8 speed with ten foot pole. Fake fixes going on since 2015 thats gotta tell you something.

Batman 357

My shudder only happens about 10% of the time. Dealer probably won't duplicate. They have a useless reputation.

mmontetx

2016 Z51 A8 here (22k miles)... I have had almost nothing but "spirited" and track driving and NEVER can remember any shudder/shutter.... That being said, I am on Forum today as I was researching a Downshift-went-wrong issue last night while playing with a crotch-rocket.
I was not going fast at the time of the incident, I was doing 35-45mph, I got into traffic, downshifted, and thats when it lertched, and rearend chirped rear wheels (from the downshift)
I am going to dealer tomorrow as CEL is on.... are these issue correlated in anyway? Demand triple-flush?

Pisswilly

I think the C7 will be remembered most for the defective A8 tranny then anything else.