dj2b4life

So I got my brand new '15 LB Z51 (8-Speed Auto) this past Wednesday! Woooohooo!!

I freakin love this car. Coming from a BMW, this was a big step for me. Glad to go American.

I have a slight issue, and trying to figure out if all Vettes do this. Upon cold starting the car, backing out of my driveway, and putting the car into drive, the car will "jerk" from Gear 1 to Gear 2. Im literally thrown towards the front of the car. After the first jerk, however, the car will not jerk again from Gear 1 to Gear 2. It's only the first time, EVERYTIME upon a cold start.

Any thoughts to chime in?
Note this is the A8.

bbrown450

I have the A6 and do not experience that "lurching".

jrainlay

I have a Z51 A8 with just over 500 miles on it and I have the same problem. I've found that when the car is cold, I can lessen this problem by starting out in manual mode and paddle-shifting to second gear at low RPMs, lifting my foot between gears and not rushing the shift. After getting through that first 1-2 gear change, you can go to automatic mode and it should be OK. Incidentally, I drive my car in manual mode almost all the time.

dj2b4life

It's interesting that you mention this. I, too, have noticed no issues in the paddle shift mode. Anyone else chime this?

Elegant1

Give it at least a 1000 miles if it's still doing it the Dealer can do a re flash of the software. This transmission has a learning algorithm sometimes it takes time to adjust properly.

Joy c7

clegg

My A8 has this a bit. Seems to be less jerky as the miles accumulate (2300 now).

seCen

Have the same exact problem. Seems like it happens majority of the time on a cold start. I have to keep the foot on the brakes for a few seconds before driving off. Have approximately 4000 miles on the car and it seems to occur in the past 1000 miles.

9ball1104

I've got a 2015 A8 with 600 miles and no problems, but there are many threads on this. There's a TSB which specifically addresses this issue and will walk you through a process to "configure" the transmission. I'm on my iPad now but I will attach it to this thread later.

9ball1104

Here's the TSB...

seCen

Will definitely give this a go tomorrow. Thanks, 9ball.

billeee

Went through the procedure. Did not work for me.

9ball1104

Sorry to hear that. Then I would take back to the dealership. When they refer you to the TSB you can tell them that you already tried it. As I recall there are things the dealer can do short of replacing parts.

767guy

This is a very common issue with the 2015 A8. Mine is up to 6000 miles now, still does the harsh 1-2 shift first drive of the day. It is not temperature related as I had the car in Florida for the winter

The "C" version is the latest ( 14-07-30-001C ) of the service bulletin that GM issued in Jan 2015. The main difference between the A version and the C version is that now for cars built after 29th of Sept 2014 with the A8 the transmission software can be reflashed at the GM dealer in a service bay without having to do the very labourious drive proceedure for clutch relearning. Hope this helps.

I think as many cars that went into storage for the winter are now coming back on the road there will probably be an increasing number of posts on this issue.

racezx9

I just posted a thread on this. I had the same issue it appeared after 1000 miles and it was very harsh all the time from 1-2 in D and M mode. I brought it to the dealer and they re-flash the computer and now everything is as smooth as can be in D and M. if you have this issue I highly recommend the dealer option under warranty. I had tried the C option and had very little success.

hawkgfr

Quote:

Originally Posted by Elegant1

Give it at least a 1000 miles if it's still doing it the Dealer can do a re flash of the software. This transmission has a learning algorithm sometimes it takes time to adjust properly.

this

Jay_Davis

Unfortunately, given time it relearns this bad habit.

10mm_

Mine went away after a few hundred miles and I am at 1500 it's not been back.

hawkgfr

I'm at 6500 and it shifts perfect since about 800 miles.

dirty eddie

I have the same problem and do exactly llike jrainlay does it.(non Z51 but A8)