NHTSA Complaint #10524623 — 2008 GMC ACADIA

AS I WAS PULLING OFF OF THE INTERSTATE ONTO ROCKVILLE RD I NOTICED THAT THE CAR UPSHIFTED FROM 3RD VERY VIOLENTLY. I THEN HIT A STOP LIGHT AND IT DOWSHIFTED PRETTY ROUGH AS WELL. I THOUGHT UH OH AND NOTICED THE CHECK ENGINE LIGHT COME ON. WHEN I PULLED AWAY FROM THE LIGHT I NOTICED THE CAR WAS MOST LIKELY STUCK IN 3RD GEAR AS THE RPMS MATCHED THE MPH AND FROM DRIVING A STICK ALL THOSE YEARS THEY MADE SENSE. I LATER FOUND OUT THIS WAS DONE ON PURPOSE TO STICK THE TRANSMISSION IN 3RD GEAR TO FURTHER DAMAGE IT AND ALLOW YOU TO CONTINUE TO DRIVE. I GOT TO WORK AND HAD ONSTAR RUN A DIAGNOSTIC. IT CAME BACK WITH A P2715 CODE FOR THE TRANSMISSION CONTROL. AFTER LOOKING INTO THIS CODE IT APPEARS TO INVOLVE THE 3-5-R WAVEPLATE THAT CONTROLS THE CLUTCH FOR THESE GEARS. I, OF COURSE, AM 6 MONTHS OUT OF WARRANTY ON THE DRIVE TRAIN. AFTER CONFIRMATION WITH GMC IT WAS THE WAVE PLATE. THIS APPEARS TO BE A COMMON PROBLEM CROPPING UP WITH THIS TRANSMISSION WHEN YOU LOOK AROUND SOCIAL MEDIA. *TR