Originally Posted by Land Cruiser

I've been thinking about it some more and I think the grinding noise was from gears. At first I thought that the branch might have got caught on something spinning, like the flywheel/flex-plate. But since it got caught on the shift linkages, it probably shifted the transmission into a different gear, or to park, or half-way between gears? The car was in gear though when I pulled over.

Never had anything like that happen before, even when off-roading (not in the 370z). Probably a lot better chance of hitting a deer, but I've never hit a deer before.

Originally Posted by Land Cruiser

I believe so. I think there is a lock/pawl/ratchet that needs to be physically engaged. This is what keeps the wheels locked and keeps you from rolling when in park.