I am looking at entry level used C7 autos. I know about the potential problems with the A8 and I am willing to accept that because I have heard such good things about how they perform. My question is how much of difference is there in the way the A6 and A8 drive. I have seen a lot more 2014 autos in my price range than 2015's. Is the A8 so much better that I should limit my search to 2015's or newer?

 

No. The A6 in the 2014 C7's was the last version and GM finally got it right. The C6 versions of the A6, at least prior to 2012, left much to be desired. I had one of those. By most accounts here the C7 A6 is excellent. No reason to avoid a good car just because of the A6.

 

I have an A8 and had a limited shudder/rpm oscillation in V4 mode (cruising on the highway) around 5k miles. The car went in for 2 days, under warranty, to replace the TC and perform a fluid flush; so far, at 11K miles, I've had no further shudder and the oscillations are much less.

So the take home here is: proceed with caution. My A8 has been wonderful, I'm a heretic in not having mastered a manual, and I'm very happy with the shifts. I would say there is a 90% chance that a car with an A8 is relatively flawless or at least only needing limited servicing. Some, however, have had recurring problems that appear more severe than just small rpm fluctuations.

 

I much prefer the drive of the A6 over the A8 even though the A8 WOT performance is better out of the box. I have owned three or four A6s and A8s over 6 or 8 different vehicles. Of course, I ended up preferring a manual in the C7 at the end of the day.

 

I purchased my 2014 C7 new with the bullet proof A6. Never a problem. Fast as hell, smooth shifting, and as trustworthy as an old hound dog. I consider each day how fortunate I was to not wait for the A8...

 

I had the A6 in my C6 but much prefer the A8 in the C7. With the A8, I almost never notice it shifting unless I push it.

I don't think the A6 supports the "Performance Shifting Mode" that the A8 does when you go to WOT.

 

I had a 2006 C6 A6 that I drove for 7 yrs/ 47000 miles that ran fine. Except for Caddy style cruising which was great. Performance driving with paddle shifters etc, was terrible as it was a first year model with no rev matching.

I bought a 2012 Caddy CTS-V A6 brand new, drove it for 4yrs/41000 miles that ran flawlessly and was a DRAMATIC positive improvement over the 2006 C6 A6. Great rev matching, faster upshifts and down shifts.

I recently traded the CTS-V in on a mint condition 2014 Stingray A6 with 6500 miles owned by an old guy like me, so I doubt it had a hard life and checking the service history, had just one minor issue ( the transparent top creaking that was fixed). I now have 9400 miles on it and the A6 works even better than the A6 in my CTS-V( faster on the upshifts and downshifts and great rev matching).

One thing you might want to keep in mind is, if you want to buy a 2014 and get an extended GMEPP warranty ( Like others on here, I highly recommend Dennis Fictner for the best price and no BS ), it has to not have run out of the OEM 3/36 bumper to bumper warranty. Best bet is to call Dennis and get the details BEFORE considering a 2014 if an extended warranty is something you're interested in.

Bottom line is, the A6 in the 2014 C7 is the last iteration that is very well developed and basically bullet proof, with the bugs worked out and many improvements made over the the first year 2006. The A8 is still having issues with the tranny, torque converter, AFM etc. The good news is, most have not had any problems, but some have had multiple problems. I kept waiting for GM to resolve these start up issues before buying a new Z06, but finally got fed up and bought the 2014 Stingray with the tried and true RELIABLE A6. Eventually I may move to a Z06, if they finally get the A8 figured out, but not till then. But that's just me. Others have already been running around in their A8 vette having a ball with no problems.

 

It supports both performance shift modes. Scared the poop out me the first time it kicked in.

 

I had a 2006 A6 that crapped out at 1500 miles in a 4th of July Parade. But GM replaced it, put in a new computer and I had over 200 1/4 mile runs in that car. It ran great in the low 12's all day long. Then I bought a 2014 C7 with the A6. This A6 is light years better than my C6's trans. But the A8's better yet even with the problems that are massively mentioned on this forum. If you stick with a newer car I'm sure it's even better and you're chances of problems should drop. Just saying!

 

With the A6 you'll be fine knowing you got a bullet proof A/T.
With the A8 you'll be looking for problems that may not exist.

 

The A6 does in fact support "Performance Shifting Mode". First time it came on, it surprised me. I thought there was something wrong until I saw the sport shift indicator light on the dash.

 

Sounds like the A6 would be fine. Thanks

 

Before submitting the A6 for sainthood nomination:

http://www.caranddriver.com/comparis...ertible-page-3

 

Amazing thing to me is that people believe Car & Driver is un biased and you can trust everything they say. Well I've been a subscriber for a long long time and it's easy to see a trend. Count on it. And it's clearly anti-anything American.

 

That has nothing to do with the A6, the 2015 A8 has the same problem. The problem is that GM lied and the car isn't track ready because they didn't have enough cooling and they knew it. When they added the cooling for 2016, the lied again and said their would be an upgrade for the 2014 and 2015, but none ever appeared, and asking about it is off limits.

Best bet is to get the A6 and add aftermarket cooling.

 

On the web I have not been able to find any news about cooling improvements during 2016. They mentioned that this was improved until 2017.

 

If I were looking for a used C7 w/ an automatic, it would be a 2014. W/ any used 2015 or later, you'll never be sure if it was traded because of an A8 issue (which abound throughout the GM product line). Google "GM A8 Transmission issues" if you need verification.

Not insinuating that a C7 w/ an A8 is going to drop the transmission on the pavement or that it will fail, just be prepared to potentially live with some abhorrent transmission behavior w/ 2015 or later C7.

 

I had a 14 Z51 with an A6 and it was bulletproof. I now have a 17 Z06 with an A8. Have not had it too long and the miles are low but so far its been fine.

 

I had an A6 in my '14 Z51 and I have an A8 in my '17 GS. In my opinion, the A8 is a better performing transmission and it runs much cooler than my A6 did in daily driving. Only thing I really don't care for is that it upshifts into 2nd while going around a corner when you take off from a dead stop.

The A8 shifts a little faster than my A6 did and the RPM stays more in the power band after upshifts since the RPM drop is not as much as the A6. Overall I am very happy with the A8 over the A6 performance wise.

If a 2014 better suits your price range, then go for it. I was happy with the performance of the one I had, and going to an A8 wasn't the main reason I switched cars. The 2014 Corvette A6 is a very good transmission in the car.

 

Price range isn't the only reason people have and should consider the A6 over the A8. Some are looking at a 2014 just because it has the A6 which is not problematic like the A8.