Shudder (Judder)
WARNING: This page is about a different car, the 2011 Jaguar XKR, 2011 Jaguar XK, 2010 Jaguar XKR, and 2010 Jaguar XK. However, it is still accessible from the selected car via links, so may be relevant.
Shudder is a low frequency oscillation of the entire steering system (tire, wheels, steering gear and linkage, etc.) when the vehicle is steered during static-park or at low speeds. Shudder is very dependent on road surface.