TDU1 : Extreme Off-Road 4x4 Physics Modding - YouTube
I don't have just this car for off-roading, it has very stiff / rigid steering, but is designed just for off-road (too bad that the map is not great enough for off-road, but you can take a winter map mod, and maybe there are also good enough map mods for off-roading)
if not, try those off-roading games B-)
Full Drive 2: Hummer - YouTube