I've run into a number of interesting vehicle glitches.
Take a Tiger loaded with HE from the hangar at the default field. Drive out of the hangar, turn right to point at the fuel dump, and blow it away. Watch the pretty flame.
Now drive over to it, and aim straight for the center of the flame. Watch your tracks get traction on the flame and start to climb, pitching your tank bow-up until any inaccuracies of aim cause it to slide off to one side. If you're good, and get aimed good enough to pitch your tank up on its tail, you'll get to listen to that mad downhill race noise as your tank falls right through the concrete.
I got a similar effect with the previous beta, having driven over to the aircraft shelters beyond the ammo dump (the structures that look like quonset huts missing each end). If I drove my tank up the side of the structure, as soon as the rear of the tank became its sole contact with the ground, it would fall through. I was able to repeat the problem with the M3, except that only the tracks fell through; the front wheels kept the vehicle from falling all the way through the ground. I am still working on duplicating this problem in beta 9; I have been able to drive the Tiger up onto the structure, but not far enough to see whether it will fall through the ground.
Update: It is no longer possible in Beta 9 to get either the Panzer IV or the Tiger to upend themselves enough on the aircraft shelter to fall through the terrain. However, when accidentally colliding with the flames from the burning fuel dump in an M3, the front wheels came off the axles, allowing the front end of the vehicle to dig into the ground. Visibly, the front wheels were bouncing up through the fenders, although they are not visible on screen shots.