Make a hole in the terrain?

I'm using the Clear Terrain tool, which makes a nice hole, but there is still collision, meaning you cant drive through the hole. Any way of fixing this?

 

I suppose you would have to edit the terrain collision data so it has the same hole too. I don't really know if this is like most games which use a collision file for the terrain, if it is then just put the desired hole in it

 

I ran into the same problem when making a hole on a mountain to create a tunnel

 

Hmmm, I've never had trouble with it, I'll go back and try again...

 

Cool, let me know of it works for you. Still havent worked it out yet.

 

Anyone know how to get it to work?

 

If you want to make the hole for a tunnel, I don't think that would work even if there was no collision in that spot. Try moving a car deep under the heightmap surface, it pops straight up. The same would happen if you tried to drive under the edge of the hole.