5.1 Toe-Differential Angle

WARNING: This page is about a different car, the 2007 BMW 550i and 2006 BMW 550i. However, it is still accessible from the selected car via links, so may be relevant.

The toe-differential angle (a) is the angular position of the internal wheel on the curve in relation to the external wheel on the curve when driving round bends. The steering is designed such that the angular position of the wheels in relation to each other changes as the steering angle increases.
In ideal cases, the wheel axes meet at point D in any steering position (except for straight ahead).

Fig 1: Identifying Toe-Differential Angle
Courtesy of BMW OF NORTH AMERICA, INC.