Park on slope - Car rolls away 2023 Denali

[Vwsportbug]

Recently parked my Acadia in a mild slope. When I returned to the vehicle it had rolled backwards about 20 feet (across sidewalk and into live traffic lane). I know that I could be using the Parking Brake but I’ve never owned a vehicle before that wouldn’t hold itself in PARK on a slight slope. Is my transmission faulty? It was in all-wheel drive at the time and definitely in PARK. Thoughts???

 

[G-126870]

Unless it was icy and it slid... take it back to your dealer immediately. In the meantime, use the parking brake if you must use the vehicle.