If your asking can MB void the vehicle warranty because an owner swaps out the swaybar, the answer would be yes, but only to the extent that the replacement swaybar caused specific damage. As an example, can they deny repair and replacement to say the emmissions systems, the answer is NO. If however, you incurr damage to the suspension system, the answer would be YES. Because it effects that system. Then, it would be up to the individual, to prove the replacement swaybar, was not the cause of that failure, during the warranty period.