I've tried every button on my gamepad and looked in the options under controls and bindings...what did I miss ?
Got my car stuck on a "curb" type structure between the front and rear tires under both doors and can't get anything to happen.
Unstuck Rocking/Rotating feature added to all vehicles. Use Left Stick or A/D W/S or LShift/LCtrl to engage rocking and rotating to stuck/beached vehicles to try and free them.