Owners with problematic A8's, please look within. (Merged Threads)
#1
Drifting
Thread Starter
Owners with problematic A8's, please look within. (Merged Threads)
so while creeping in a line of Corvettes staging for the Bloomington a Gold road tour I had the trans in sport mode was turning into a parking lot at low speed when the trans clearly disengages on its own like putting the car in N while in drive the engine revs up and WHAM the trans drops back in with a giant forward lurch. Am I doing something wrong? This felt really scary.
Last edited by Black&White; 06-28-2015 at 01:05 AM.
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03-10-2016, 11:52 AM
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Go ahead read all the posts here by other owners then read the comments by that sack of crap chief engineer saying what a stable reliable transmission the A8 is. Folks get your heads out of the sand and open your eyes EVERY single A8 made before October of 2015 was made exactly the same way. If you have any of the rough shifting or delays to gear YOU OWN a DEFECTIVE transmission and it WILL start to FAIL in time and GM will DO NOTHING just like the ignition recall that killed so many people. Do you have any idea what it would cost GM to replace or repair Several HUNDRED THOUSAND defective A8s now in GM cars and Trucks? This is why they won't own the defects my friends. Well I intend to change all that.
By the way will you loan me your Corvette to drive while mine spends weeks and weeks in the service department while GM gives the dealership endless instructions on how to try and do band aid repairs so they don't have to pay for properly repairing it? It would be so kind of you..Thank You.
I also hope that you do not make a public spectacle of yourself at the Bash. I think the better approach is to try to have a private meeting with whomever you want to express your concerns to. However, it is a free country and you are free to express your concerns publicly if you wish. But I too have this right and, should you take this route, will personally stand in rebuttal and share your own words from this public forum that show your lack of cooperation with GM to actually repair your transmission. Regardless, I truly hope you and GM can work out a satisfactory solution in the end.
#3
Melting Slicks
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A8 does display some unusual behavior when operated at slow speeds with lots of stop and go. While some descriptions may not match your exactly, fairly confident it falls into the same category of reported odd behavior.
Wonky for sure, but likely caused by the same adaptive learning feature included with the C7 and A8 tranny. Unlikely you'll be able to recreate that same behavior if you try (more likely it will do something else a bit odd if you keep at it).
The C7 is most certainly not a parade car IMO.
Wonky for sure, but likely caused by the same adaptive learning feature included with the C7 and A8 tranny. Unlikely you'll be able to recreate that same behavior if you try (more likely it will do something else a bit odd if you keep at it).
The C7 is most certainly not a parade car IMO.
#4
Drifting
Thread Starter
A8 does display some unusual behavior when operated at slow speeds with lots of stop and go. While some descriptions may not match your exactly, fairly confident it falls into the same category of reported odd behavior.
Wonky for sure, but likely caused by the same adaptive learning feature included with the C7 and A8 tranny. Unlikely you'll be able to recreate that same behavior if you try (more likely it will do something else a bit odd if you keep at it).
The C7 is most certainly not a parade car IMO.
Wonky for sure, but likely caused by the same adaptive learning feature included with the C7 and A8 tranny. Unlikely you'll be able to recreate that same behavior if you try (more likely it will do something else a bit odd if you keep at it).
The C7 is most certainly not a parade car IMO.
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ron landgraf (10-27-2016)
#5
Was the air conditioning on or had you just started turning the steering wheel when that happened? Perhaps the load on the engine changed just a little from either one of those things.
Last edited by WelderGuy; 06-28-2015 at 01:16 PM.
#6
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#7
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Ahem... I have a C7. I have the A6. Maybe an A8 ain't a parade car but...
I do parades!
A C7 can do parades with the manual transmission too! I did many parades with my 2007 M6.
Sweeping statements can cover too much ground and might not be totally accurate!
Elmer
Last edited by eboggs_jkvl; 06-28-2015 at 03:43 PM.
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Pat7211 (05-01-2016)
#8
Melting Slicks
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Mine has displayed this behavior on a couple of occasions in the stop and go traffic especially when the line starts to move and you apply gas and then have to apply the brakes.
Manual Tranny should be no problemo. But the accordion motion of parades would not be an A8 C7's strong suit.
#9
Drifting
Thread Starter
AC was on yes.
#10
Just a guess, but why do you have it in "sport" mode when you are toddling along at an idle?
Typically, most autos are programmed to start in 2nd gear for smooth operation and partial-throttle fuel economy.
When placed in the more aggressive "sport" mode, a partial-throttle downshift into 1st is more likely. I suspect what you are experiencing is a downshift into 1st.
Put it in "touring" or "street" mode and see if this happens again in the same situation.
Typically, most autos are programmed to start in 2nd gear for smooth operation and partial-throttle fuel economy.
When placed in the more aggressive "sport" mode, a partial-throttle downshift into 1st is more likely. I suspect what you are experiencing is a downshift into 1st.
Put it in "touring" or "street" mode and see if this happens again in the same situation.
#11
Melting Slicks
I make no claim to be a transmission expert but excusing that sort of behavior by calling it “adaptive” seems a lame excuse.
My son has a Dodge pickup with an 8-speed, he’s had no “adaptive” issues and the C7 shouldn’t either. C7 transmission less functional than a pickups??? Don
My son has a Dodge pickup with an 8-speed, he’s had no “adaptive” issues and the C7 shouldn’t either. C7 transmission less functional than a pickups??? Don
#12
So far I am less than thrilled with this A8. I only have 200 miles on it so far but to be honest if I could trade for my 2014 A6 I'd rather have it. Hopefully it gets better with some mileage. So far not very impressed compared to the A6. I'm hoping nothing is wrong with it but my instincts are telling me this can't be right, adaptive learning or not.
#13
Drifting
Thread Starter
So far I am less than thrilled with this A8. I only have 200 miles on it so far but to be honest if I could trade for my 2014 A6 I'd rather have it. Hopefully it gets better with some mileage. So far not very impressed compared to the A6. I'm hoping nothing is wrong with it but my instincts are telling me this can't be right, adaptive learning or not.
Last edited by Black&White; 06-28-2015 at 11:15 PM.
#14
Race Director
I make no claim to be a transmission expert but excusing that sort of behavior by calling it “adaptive” seems a lame excuse.
My son has a Dodge pickup with an 8-speed, he’s had no “adaptive” issues and the C7 shouldn’t either. C7 transmission less functional than a pickups??? Don
My son has a Dodge pickup with an 8-speed, he’s had no “adaptive” issues and the C7 shouldn’t either. C7 transmission less functional than a pickups??? Don
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Gonzo (07-17-2016)
#15
so while creeping in a line of Corvettes staging for the Bloomington a Gold road tour I had the trans in sport mode was turning into a parking lot at low speed when the trans clearly disengages on its own like putting the car in N while in drive the engine revs up and WHAM the trans drops back in with a giant forward lurch. Am I doing something wrong? This felt really scary.
I have read all of these A8 threads with great interest, and seen lots of advice to race into the dealer for a reflash. Instead, I might suggest to those who have experienced this to give it some miles and let the learning process work itself out. Just my 2 cents, I am no expert. Thanks
#16
Racer
Just give it a little more time... I'm saying that from the A6 cheap seat right now, but I know my luck & am confident the A8 will be the showcase tranny to have since I didn't hold off & get a 2015.
In the meantime, I agree with the others put your drivers mode into Eco, Tour, or Weather while in traffic or in stop/go situations. Check with your dealer for any TCM updates to the tranny frequently. If you do get an update, ask the Dealer for a copy of the TSB or any info. they'll give you & share with all of us on the forums.
As a last resort, you might ask your dealer if they can clear the ECM/TCM of all learned/adaptive data. This could set your car back to the day you bought it & you could prevent it from gathering & applying stop/go operations in Sport mode & so on...
The A8 is nothing lame, it's as much of a change as Direct Injection is to Port Injection. The A8 is always in the power band for the right gear given the torque demand & vehicle speed, what your missing is the tradition sounds of an engine's redline, momentary pause, then into the next gear. I'm glad that Chevy didn't inject engine noise into the cabin or in the speaker system, like some other mfgs. are doing now. I mean how are we suppose to hear some not operating right if they're creating sounds to cover it up with in the first place?
Wormwood
In the meantime, I agree with the others put your drivers mode into Eco, Tour, or Weather while in traffic or in stop/go situations. Check with your dealer for any TCM updates to the tranny frequently. If you do get an update, ask the Dealer for a copy of the TSB or any info. they'll give you & share with all of us on the forums.
As a last resort, you might ask your dealer if they can clear the ECM/TCM of all learned/adaptive data. This could set your car back to the day you bought it & you could prevent it from gathering & applying stop/go operations in Sport mode & so on...
The A8 is nothing lame, it's as much of a change as Direct Injection is to Port Injection. The A8 is always in the power band for the right gear given the torque demand & vehicle speed, what your missing is the tradition sounds of an engine's redline, momentary pause, then into the next gear. I'm glad that Chevy didn't inject engine noise into the cabin or in the speaker system, like some other mfgs. are doing now. I mean how are we suppose to hear some not operating right if they're creating sounds to cover it up with in the first place?
Wormwood
#17
Racer
I have read all of these A8 threads with great interest, and seen lots of advice to race into the dealer for a reflash. Instead, I might suggest to those who have experienced this to give it some miles and let the learning process work itself out. Just my 2 cents, I am no expert. Thanks
Last edited by vettekat2007; 06-28-2015 at 11:55 PM.
#18
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Does not sound like a normal operation to me. I would get the car checked out - and hopefully the techs can get it to replicate the problem you experienced.
#19
so while creeping in a line of Corvettes staging for the Bloomington a Gold road tour I had the trans in sport mode was turning into a parking lot at low speed when the trans clearly disengages on its own like putting the car in N while in drive the engine revs up and WHAM the trans drops back in with a giant forward lurch. Am I doing something wrong? This felt really scary.
I’m sorry you’re having transmission concerns with your Corvette. I completely understand how frustrating it may be to not know what could be going wrong with your vehicle. Have you brought these concerns to your dealership’s attention? I see forum members are offering advice, but if you decide to reach out to your dealer, feel free to send us a private message with your contact information, VIN/mileage, and preferred dealership.
Kindly,
Julie C
Chevrolet Customer Care
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Not meaning it isn't pretty enough for parades, just the A8 auto with the slow speed start and stopping can cause those unwanted lurches.
Mine has displayed this behavior on a couple of occasions in the stop and go traffic especially when the line starts to move and you apply gas and then have to apply the brakes.
Manual Tranny should be no problemo. But the accordion motion of parades would not be an A8 C7's strong suit.
Mine has displayed this behavior on a couple of occasions in the stop and go traffic especially when the line starts to move and you apply gas and then have to apply the brakes.
Manual Tranny should be no problemo. But the accordion motion of parades would not be an A8 C7's strong suit.
When I do a parade with this car, I'll have it in manual and basically locked in to 1st. I don't have any need for any kind of shift while I'm doing 4 mph in a parade with a pretty looking lady perched on top of my waterfall!
Unless I want to see her do a one and a half off the back and stick the landing!
Elmer