Trawling through STEAM the other week and found a game by the name of Spintires which came out last month. http://store.steampowered.com/app/263280/
The game is made by the same mob who did Offroad racing however it's a little more refined.
The objective of the game is to get a certain number of logs (loads) from one end of the map to the other.
As simple as it sounds it can be extremely challenging and frustrating - I have had to walk away from the PC before I broke something.
The physics is good so is the real-time deformation and fracture in game environment.
There are quite a few videos on Youtube of the game play if you are interested.
Best of all you get to drive some fun vehicles!
Features include- 4wd activation, diff locks and winch points.





There are also plenty of mods for the game. Meaning you can get an array of vehicles if you just want to play around


For $30usd it aint bad value.
Get a couple mates into it and have yourself a virtual off road adventure!
Anthony