In 67852 I hoped that Continuous Speculative collision would create incorrect behaviour in a good way (it tends to make things more "floaty", which could be good for a snowmobile). Sadly it created incorrect behaviour in a bad way (e.g. driving off the edge of the downward slope would push the snowmobile upward). Switching to Discrete, but we'll need to be wary of high speed collisions.
When a snowmobile moves from a snowmobile-allowed surface to a not-snowmobile-allowed surface, increase the drag slowly instead of instantly. Helps with situations like driving on rocky snow (where the player is often switching to rock and back).