The model was made using primitives and extrude, boleans and the ground plane in Zbrush with a rolling brush for the tyre tracks.
Rendered with a simple directioal light and final gather. shader has Ambient occlusion pluged in to the diffuse to pick up details.
The sky backgroun is my own texture applied to a nurbs surface behnd the scene.

I have run out of time so it is not finnished I wanted to add mud splash and break up the surface by importing into Zbush and roughing up, but sadly no time. I have to work on someone elses stuff Boo Hoo.