What 389 owners told NHTSA about the 2018 GMC Acadia Denali

The vehicle has experienced repeated electrical and engine-related malfunctions, including random engine shutdowns while driving and random no-start conditions. The thermostat and cooling system failed and were replaced in 2024. Multiple sensors have failed. The braking system remains noisy even after brake replacement. The lane detection safety system does not provide audible alerts. The vehicle is currently operational and available for inspection upon request. How was your safety or the safety of others put at risk? The vehicle has randomly shut off while driving on both highways and city roads in Azle, Texas. This occurred while my two children were in the vehicle. When the engine shut off, there was a risk of losing power steering and braking assist, which could have caused an accident, especially at highway speeds and in traffic. Has the problem been reproduced or confirmed by a dealer or independent service center? The thermostat and cooling system failure were confirmed and repaired by a service center in 2024. Electrical and sensor issues have occurred repeatedly but have not been fully diagnosed or resolved. Brake noise persists despite replacement. Has the vehicle or component been inspected by the manufacturer, police, insurance representatives, or others? UNKNOWN. The vehicle has been serviced by repair facilities, but the manufacturer has not provided a definitive diagnosis for the engine shutdown and electrical failures. Were there any warning lamps, messages, or other symptoms prior to the failure? When did they first appear? Yes. Various warning lights and symptoms appeared prior to failures, including cooling system warnings and sensor alerts. Electrical issues and battery failures have occurred repeatedly, with batteries lasting only 2–3 years. Symptoms began after purchase and have continued throughout ownership. Additional details The brakes have been noisy even after replacement, and the lane detection system does not produce audible warni

NHTSA ODI 11716369

Sold 2018 GMC Acadia by LEE GMC in auburn. Acadias shift to park was defective, dealership replaced before sale did not disclose, shift to park and transmission malfunctions occurred. I returned Acadia to the dealership several times and they would never properly fix or address my concerns now my vehicle is unsafe to drive. I have documentation to support the claims in my letter, I can send as well if you’d like. Thank you Will send attachment

NHTSA ODI 11647553

VEHICLE WILL NOT ACKNOWLEDGE THAT IT IS IN PARK. FORCES ELECTRICAL TO STAY ON, AND SOMETIMES WILL NOT ENGAGE PARK SO VEHICLE CAN MOVE AS IF I'M NEUTRAL. HAS THUS FAR HAPPENED WITH VEHICLE STOPPED, BUT YOU CAN SOMETIMES SHUT OFF ENGINE AND EXIT VEHICLE WHEN IT IS NOT IN PARK AND CAN ROLL AGAINST YOU, OR ON KIDS EXITING ETC. VEHICLE ROLLED IN GARAGE AND STRUCK, AND COULD HAVE CRUSHED CHILD AGAINST DOOR.

NHTSA ODI 11315398

TL* THE CONTACT RENTED A 2018 GMC ACADIA. WHILE THE CONTACT'S FRIEND WAS DRIVING 40 MPH, THE ENGINE REVVED AND THE VEHICLE ACCELERATED ON ITS OWN. THE BRAKES FAILED TO STOP THE VEHICLE. AS A RESULT, THE VEHICLE DROVE THROUGH A PARTITION AND CRASHED INTO A BRICK WALL. THE AIR BAGS DEPLOYED. ALL FOUR OCCUPANTS IN THE VEHICLE WERE INJURED AND RECEIVED MEDICAL ATTENTION. THE CONTACT SUFFERED CHEST PAIN, ANOTHER OCCUPANT SUSTAINED A CUT ON THE HEAD, AND THE OTHER TWO OCCUPANTS SUFFERED FRACTURES. A POLICE REPORT WAS FILED. THE DEALER AND MANUFACTURER WERE NOT CONTACTED. THE CAUSE OF THE FAILURE WAS NOT DETERMINED. THE VEHICLE WAS DESTROYED AND TOWED TO A TOW LOT. THE FAILURE MILEAGE WAS UNKNOWN. .*BF .*BF 'PARTS OF THIS DOCUMENT HAVE BEEN REDACTED TO PROTECT PERSONALLY IDENTIFIABLE INFORMATION PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6).'*JB

NHTSA ODI 11190983