I'm in the market for an auto c7 in the 40-45k range. This mostly limits me to early years but should I just stick with the '14 to avoid the issues of the A8 even though it's really nice on paper? I won't have any substantial warranty so it seems like a terrible transmission from a longevity standpoint. I know you hear about problems more than good things so I get that it's not THAT widespread but I know it's more widespread than most problems people complain about. Any input would be helpful.

 

I have a 2015 a8 with 43,000 on it and no problems , there were 115,000 A8 cars made , you only hear of the ones that had a problem on this forum as no body complaints "Darn my A8 is running great"

GM also uses the A8 in other car lines , asked the dealer or owner if the fluid flush was done , if not then ask the dealer to do it

Drive the car on the highway during a test drive , set the cruise control and then listen and pay attention .... does it feel like rumble strips , is the MPH varying by up and down . If not .... buy the car and buy a range device ......

Dave

 

The odds are FAR and away in your favor of getting a good one, as opposed to a bad. Or, if you are that skittish just buy an M7 and forget the whole issue entirely.

 

There is a class action lawsuit over it:
http://gmauthority.com/blog/2019/04/...ission-defect/

 

I would consider buying a used C7 with an A8 on the condition that the seller pick up the cost of performing the triple flush with the new Mobil 1 trans fluid GM is recommending. Give that puppy a test drive and see how it runs.

 

Thats the reason I bought a 2014, I wanted an auto so my wife can drive it and did not want to deal with the A8 possible issues

 

I recently purchased a used C7 and was not aware of the A8 complaints but for me the manual felt like it had better gearing and the auto felt slow in manual downshifts. I went manual. If you go auto as someone suggested get the service records ad see if the owner has taken it in for the shudder complaints. I would also as someone suggest get the most recent fluid.

 

Purchase one that already had the torque converter changed. Then install range device. I went with a 2014 then did complete widebody conversion. I still use range device to stay in V8.

 

Same here.....

 

I have 2 C7 A8's.

My 15' Z51 was purchased new and now has 21K. It never had a shifting problem as described in the lawsuit. However, I had a rumble when in V-4 mode caused by the Torque Converter. It was replaced at 7,500 mi. Rumble came back at 14K and dealer changed Tranny fluid. No noticeable problems since. This car now lives only in IA.

Last Sept I purchased a used 16' with 34K. Car was immaculate and in a quick 2K of driving had no issues. However after we returned to Florida for the winter, after a month or so, I got the same rumble as my 15' when in V-4 mode. This time same FL dealer changed Tranny fluid to a new special Mobil 1 product that has been designed specifically for GM A8. Took 6 wks for appt due to all the vehicles they were having same issue with (4 a day 6 days a week). No problems since but I immediately bought a "Range" plug in to keep vehicle from going into V-4 mode.

We have 3 A8's in our local Vette club here in IA and 2 of us have had this issue and both more than once (doesn't count my FL A8). Very easy solution is an ECM flash to eliminate going into V-4 but GM can't do it because of FED regulations. If I do it, flashing will cause GM to void engine and drive train warranty, so Range was only short term answer. Once at 5 yrs, believe me, they are getting flashed! From what I am told, the computer causes the tranny to constantly have T/C going in an out of lockup to maintain V-4 mode, and some of them just can't handle it. Besides, who really want's to drive in V-4 mode anyway! Really doesn't save gas unless you are on a flat road for miles and miles and going under 70.

Other than this, my trannys have always shifted flawlessly, After sitting for a couple weeks without being driven, they may not start moving after putting them into reverse, without extra throttle, but I don't see this as a real problem. Remember, transmission is programmed to learn one's driving habits and shifts accordingly.

 

thanks for the extra details. im looking at a 16 this weekend and if i take it home, the range is going in before i drive it off the lot.

 

FWIW the A8 in the gen6 Camaro SS has the exact same issues as the C7, tons of posts on it over on their boards. That's gotta be part of why they started putting the A10 into the 2019 and up Camaro SS to match the pre-2019 gen6 ZL1. I'm not an auto guy so personally wouldn't own an A8 and given the issues with the 2014s overheating I'm not sure I'd go that route either but if you don't track it that's likely a non-issue. I've read tons of posts of folks who had the TC swapped and installed the range device with good success ridding themselves of the shudder so that is something I'd be prepared to do if you have the shudder.

Personally, if I wanted an auto and a car that performs similar or better than a C7, I think I'd look at a used 2017-2018 ZL1 A10 car instead of a 2014 C7, you can get those cars with low miles still under warranty for $50k. No overheating issues and no trans shudder. It's not a Vette though!

 

Friend who has owned 50 plus new Corvettes purchased a 2019 ZL1 Camaro (non-1LE) with A10. Loves the car. Says he will get more and stay away from new mid engined Vette for a couple years. Needs more luggage space for his business. He had several A8 Vettes and other than the slowness going into reverse, he never had any shudder, or at least he didn't notice it.

As for my shudder issues, the 15' with electronic differential had a different shudder feel than my used 16' 2LT with mag ride but no electronic differential. It was less pronounced in the 16'. If one lives in a relatively hilly area and doesn't cruise the interstates continually, one might neot notice the shudder issue in a non-Z51 A8. Range is great! I did buy mine new to make sure I got the latest edition (spring 19'). I moved it north and will take it back to FL in a couple months.

Not sure that T/C needs to be replaced and I'm not convinced that the 4th version GM A8 T/C has created really solves the problem. The new Mobil 1 fluid probably does as good a job. Replacing the T/C involves removing the entire rear drivetrain including the torque tube. It's a 20+ hour job. If not done correctly, I feel it could cause other issues. Definitely make sure a full alignment is done afterwards. Flush actually is done 3 times with tranny pan removed/cleaned and filter replaced. (Per Hendrick-Naples service dept.).

 

I would only buy one if the trans has had the flush with new spec fluid change and/or TC swap. Silverados have the problem. Cadillacs have the problem. It’s a known issue. A friend just had the problem on his 45,000 mile GMC Sierra. The mechanic told him he has personally repaired dozens of trucks.

DOD/AFM is the culprit. You can thank CAFE rules and GM’s brilliant solution for these issues. DOD/AFM was the stupidest design automotive engineering has ever created. Great on paper and awesome while it works.