1. Make a box and lift it in the vertical (blue) direction.
2. Add two boxes to hold the back wheels. Copy the first box (Ctrl+Move) to make the second.
3. Make a third copy of the box and move it to the front centre. This box will be attached to the steerable wheel.
4. Add a servo on top of the steerable box with the servo's axis pointing vertically up.
5. Make the servo, the top box, the two back boxes BUT NOT THE STEERABLE BOX into a group. The steerable box has to be able to turn independently of the main group.
6. Add wheels to the bottom edge of each of the three small boxes. The front wheel should not quite touch the top box so that it does not rub against it.
7. Now use the joint connector to connect the servo to the front box. Click the servo then hold down the Ctrl key and click the front box.
8. SAVE YOUR WORK then add a solid floor and test your animation. The servo should work but the vehicle is not yet motorized...
9. Select the front hinge and open the User Interface (UI). Set the accel and damp values to 20 to give a motor effect...
10. Test your animation.

Let's replace the front hinge with a motor joint - this will allow us to adjust the motor's speed during the animation.

11. Select the front hinge and delete it. Replace it with a motor joint.
12. Use the joint connector to connect the motor joint to the front box (select the motor then Ctrl-click the front box).
13. Does your vehicle go backwards? If so then use the UI to change the accel value of the motor from 1 to -1.
14. SAVE YOUR WORK!
15. Test your animation.

Check out the 6.5 minute video below! It's even available in HD if you click the HD button, and you can download it from www.vimeo.com if you want!