Im not sure about 40km/h but there speed is something you have to see to believe. Once we were standing beside our car on a road inside a national park and a wombat came trotting along the road and passed us.

I ran along behind it for a while for fun , then it took off like a rocket and left me for dead. It then veered off the road and crashed through the bush into a gully like a bowling ball or sonic the hedgehog. All we could hear was the sound of breaking trees.