Last update: Monday 31 October 2016

Home > Building tips > Parts > Differential


Wednesday 16 September 2009, by Clement, Nico71

Description :

Differentials are a useful lego part that is used many times when building a vehicle. It improves the contact between the driving wheels and the soil, thus improving the vehicle’s performances.
differential_2 {PNG}


It is usefull in every vehicle. As you turn, wheels don’t spin at the same speed and without a differential, you introduce a stress on the axles : wheels tend to spin at the same speed but the soil prevents it. Having a differential reduces stresses in the axle.


However, many people in lego truck trial building don’t place differentials at their regular place in the vehicle. In fact, imagine a wheel is traped in a hole and the other doesn’t grip that much on the soil, the vehicle won’t move forward or backward.

Placing a differential in the middle of the vehicle could be usefull and realistic. However, the same problem appears : what if, due to the weight of come elements (battery box for example), the rear is heavier that the front, and rear wheels are trapped ? Your vehicle won’t move neither.

These are the reasons differentials are often left away in lego truck trials.

Additional stuff:

There exist different kind of lego differential. Old and new ones. Each has its own advantages but also drawbacks ...

For example, this is the first lego differential, the oldest one.
differential_1 {PNG}