For the optimization of driving behavior (see lecture "AE-II"), wheel toe and/or camber angles are often set between the wheels and axles. This increases the wheel resistance since they produce the same effect as a wheel running under a slip angle.
Wheel Toe
The wheel toe angle → is the angle between the vertical wheel planes of an axle and the vertical plane of the road, measured on the horizontal plane of the road. This induces a slip angle on every wheel even in the absence of an external lateral force on the vehicle. A component of the lateral force contrary to the driving direction results.
Analogous to the slip angle, the wheel resistance of a wheel under toe is given by:

Eq. 1-20

For the wheel toe resistance of an axle this value has to be doubled.