A Montana bear is apparently graduating from picnic basket theft to grand theft auto … opening up a car door and jumping inside in a shocking new video.

We’ve obtained an exclusive clip of this grisly grizzly walking right up a driveway in Whitefish, MT, Friday night around 9 PM local time … strutting up to the door and letting himself inside.

It’s hard to tell exactly what this wild criminal is up to … but he rattled around in the car for a while — before heading on his merry beary way. In his defense, maybe he thought it was his Su-bear-u.

Sources tell TMZ … this four-legged fiend didn’t damage the car other than leaving mud and leaves around the door handle — and the car’s owners only realized what happened after they found the door ajar and checked security footage.

We’re told a few bears have been wandering this neighborhood for a little while now … and they’ve also entered some of the local garages — probably looking for a snack.

Local authorities are working to relocate them to nearby Glacier National Park … though it seems that plan is moving at a glacial pace.