Wheeled vehicle surface detection

I would like to know how I can make my wheeled vehicle’s wheels detect the ground surface from a raycast and then change the friction, speed, and damping rate etc. Clearly UE4 does not allow you to modify wheeled vehicle values on runtime for some reason, how can I make this work?

I do not want to make a car from scratch by adding wheels and the body separately

Couldn’t you just use the physics material system to do this. You should be able to detect type of surface and then do your friction calculations

Yes i could, but the problem is I cannot change the PhysX wheeled vehicle properties with blueprints