Wheel Controller 3D v3.0 Demo
Wheel Controller 3D is a complete alternative to the Unity's inbuilt wheel collider. It allows for more realistic vehicle behavior, complete customization and 3D ground detection. Now with completely reworked physics for v3.0.
WebGL Demo: http://nwhcoding.com/index.php/wheel-...
Asset Store: http://u3d.as/Cu6
Also check NWH Vehicle Physics 2: http://www.nwhvehiclephysics.com