A8 Transmission failure tracking
 

There have been a lot of threads around the A8 failures. There was also a Poll. Thought it might be good to create a Google Sheet to track this stuff, could be good for Ask Tadge at some point or some other way to get data to GM in regards to the failures.

Open to suggestions on structure, I can handle making those adjustments. But this sheet is open to all for editing, so if your Forum User name is not listed, you can add it. If it is listed, you can update your response if needed.

There is a chart tab as well that has some data based on the April Poll results, but this will update with new data of course.

REPEAT: BEFORE UPDATING THE SPREADSHEET: Please search for your user ID, if it is already there, update that row. If not, you can add yourself to the end.

Google Sheet
https://docs.google.com/spreadsheets...it?usp=sharing

Chart of data
Current charts are in the Charts tab on the spreadsheet. These images of the charts were updated August 12, 2017

https://cimg3.ibsrv.net/gimg/www.cor...6d3167b2a0.jpg

https://cimg1.ibsrv.net/gimg/www.cor...2382ceab3b.jpg

https://cimg4.ibsrv.net/gimg/www.cor...4a868f2d35.jpg

Very nice!

I'll update it soon. My 2017 started shuddering at 3200 miles.
Triple flush took care of the problem, but I'm keeping the Range unit plugged in for now.

Update done. Thanks

Well done! Let's see if this goes anywhere, but great effort.

:iagree: Excellent! :cheers::thumbs::cheers:

Thanks, nice to see much of the data compiled.

great idea!

Just an suggestion for the graph above. Since you have "No Failure" and then two columns that break out the failures, add a column of Combined Failures next to No Failures.

You might also consider including engine type (LT1 or LT4) since the torque converter failures aren't showing up in quantity in the Z06 forum.

Yes, good idea. I showed "Date of Failure" as the date in shop, not when first symptom noticed. Symptoms were sporadic at first, then in Nov. 2016 started to get worse and could be demonstrated at any time.

Thanks for the updates folks, I'll be doing some cleanup of things after people update; remove duplicates, data format consistency, stuff like that.

Once we can get some of the previous folks to update dates and mileage info we can start to see if there are any trends.

So far, as mentioned by others previously, it really seems to show that the issue is more with the torque converter than the transmission, failure rates on those seem to be much greater. And most of those seem to be with the 2015's at this point.

Gets my vote for Thread of the Month.

I added a column for model (Stingray / Z51 / Grand Sport / Z06) so if you get a chance, pop back in there and update. And some of the columns have drop downs to enter data, just click on the little arrow and you can pick from the list.

very cool indeed!

Would the delayed engagement (o-ring) problems described in #16-NA-014 be considered a problem with the transmission? They wouldn't be linked to the TC, IMO.

Even the 2017 reported failure rate according to those data is around 15%. Now granted, it's probable that people with no problems likely reported less than those with, but even cutting that number down to 5% is way too high for a single component in a modern vehicle.

I think this is a good idea - will still have some bias, but should provide a more accurate picture than anything we've done so far.

I'll look at this and fill in my part later this weekend. Several forum members, including me, have had (or do have) more than one C7. Will this allow us to put both experiences into the database?

Also, some might fill out the database as 'no failure' now, but will want to update later if they have an issue. Will this allow that scenario?

Thanks, Paul

Good point in regards to multiple C7's.

If that is the case, append a - 1 and a - 2, etc., to your forum name and list each one separately. This way I won't prune you out of there as a duplicate like I have already for some I have seen listed twice.

I'm older and a little forum computer challenged how do I respond?

I'm on an iPad and looks like it's prompting me to download an app to respond to the spreadsheet. I doubt I'll do that so I'll just add that I've got a 2015 with 7,800 miles A8 and when it's cold I always use paddles till it warms up but no failure yet.

Bingo.

FYI iclick, an o-ring issue is not necessarily the problem with the delayed engagement. GM's stance is that the TC is leaking down due to the veins in the stator support plate not having adequate check balls to stop fluid drain back. the result is delayed engagement while the TC fills and pressurizes.

The actual fix for the stator shaft replacement is not an o-ring, but complete replacement of the stator support plate as changes in the casting were made a new part released to facilitate an additional check ball. As part of the change, normal seals/orings etc are changed out for good measure per the TSB.


There needs to be the following change to the overall structure IMHO:

1. Failure is a strong word, and can be interpreted quite differently. For example, some may interpret as a complete replacement of the Torque converter or transmission. I would reword to "Issue'' or "problem", and define as a dealer acknowledged issue, not just "i think there is an issue".

2. Although my TC is failing as well, my main issue at this current moment is the delayed engagement as mentioned above. It's hard to classify as a failure of either as the exact issue has not even been identified by GM yet (the current fixes do not work). At best it's an issue related to the transmission, not the TC as previously thought by the braintrust.