It's a simple car with 4x4 wheel drive and two speed gearbox. The car is equipped with two differential but hasn't suspension, so I had to take a commuter on the front system, so you can practice steep terrain. The gearbox is very small, but is manual, although it is very easy to change. It is also equipped with a lighting system connected to the wheels, and of a reinforcement under the car in order to protect the gears, all controlled by a SBrick. I'm sorry for the bad writing because I'm Italian. Commented, I hope you enjoy!
The transmission is structured as follows: the blue axis is the input and the green axis is the output. The central axis and is movable. In the first picture is inserted the first gear with a ratio of 0.3:1 (very powerful but not very fast), while in the second picture is inserted the second gear with a ratio of 1:1 (very fast but with very little power).