2016 ATS-V Transmission Rough shift and Slipping

**ItzaBerly** · 03-08-2017, 03:59 PM

My 2016 automatic ATS-V sedan has been shifting rough since i purchased it with 1800 miles on it . It is worse at low gears esp around 30mph mark. I took it in for a check and because the battery had been recently disconnected, I was asked to drive it and allow for the adaptive learning. several hundred miles later i felt no improvement, indeed thought it may be worse and returned to service. They could find nothing wrong/no codes and again suggested to keep driving. while driving in sport mode yesterday, I tried to hard accelerate after reaching around the 25 mph mark, it acted as if the xmission slipped. I got no power, engine revved RPM's zoomed to at least 6000. i decelerated to 15 mph and tried again to accelerate. the same thing happened. no additional power but engine revved up. after coming to a stop and shifting to park and back into drive i had no problems at any speed.
Thanks for sharing any knowledge. My girl is sick and she needs some help.
Berly

**Hib Halverson** · 03-09-2017, 03:17 PM

I want to make sure I clearly understand the problem.

When someone tells me an automatic is shifting "rough" that means to me part-thtottle shifts are very abrupt or "jerky" and/or uncomfortable, however...your problem sounds like the trans is either slipping or even freewheeling between gears on upshifts.

I know there have been problems in the field with 8L90 torque converters failing.

This dealer who tells you to keep driving...did they road test the car in an attempt to duplicate the problem you are having? If they did not, try going back to the dealer and either taking their service advisor for a ride or let him drive and you go as a passenger to identify when the car "acts up".

As for "adaptive learning" there is a way to "force" the trans controller to "relearn" but the procedure is quite complex and requires driving the car in a very specific manner.

I can post the procedure if you want but I think I'd first take the car back into the dealer and have them road test it to experience the "slipping" characteristic you've observed before I'd do anthing else.

**ItzaBerly** · 03-15-2017, 08:43 PM

The service report says that it was road tested (i did not go along). It also says, no codes found, fluids and condition found ok, and no bulletins. The slipping event has only occurred once, but it was exceedingly apparent and could not be considered normal. The hard jerky shifts are often and easy to duplicate. I'll take your advice and go for a ride with. Thanks for your response, I'll update if I get clear answers or clearer questions.

**ItzaBerly** · 03-24-2017, 08:34 PM

I have had two more incidences of transmission getting stuck and not shifting into the next gear, its happening at about 35 to 40 miles per hour. it has occurred twice now in the exact same scenario of, entering a hard right turn at 25 to 30 mph and heavy acceleration out of the turn. the car shifts up once then just stops pulling and revs rpm's. I let the car speed go back down to 30 to 35mph and then it drove home fine.

**Hib Halverson** · 04-01-2017, 10:53 AM

I'd go back to the dealer and complain, again.

That the problem is consistent in right turns with hard accel at the exit leaves me with a sneaking suspecsion that maybe the trans fluid level is low. It's very difficult to check the fluid in the 8L90. The procedure is in the Service Manual and requires a lift or the car perfectly level on jack stands. You have to be under the car with the trans fluid warm and the engine running to check it.

I've done the procedure with our other ATS-V which has the 8-spd and it's a PIA.