Your BMW tie rod is the part of your steering system where the alignment of your front wheels is made along with the part that actually moves the wheel in the desired direction as inputted by the driver. The tie rod is a simple bar with a ball joint fitted to one end that has a stud protruding from it. The stud on the ball joint connects to the spindle of the BMW so a secure connection can be established and pressure can be applied to actually turn the wheel in the direction desired. The other end is screwed into a bar that is connected to the other tie rod that is connected to the wheel on the opposite side of the vehicle. If a BMW tie rod is worn out it will be felt in the steering wheel of the vehicle. There could be a slight movement from the wheel that feels like it is shaking or the turning motion of the vehicle may seem less responsive than before. If either is felt an inspection by a qualified BMW technician is recommended. The tie rod is the part in which the toe or the inward and outer alignment of the wheels is positioned can be adjusted. In most instances, if one or both of them on your BMW are changed, an alignment of the wheels is recommended. This will help to reduce wear on your front wheels and keep your car running straight down the road. A tie rod very rarely wears out but they can be damaged if a curb or other obstacle is hit by the wheel. It also only takes a slight misalignment of this part to cause excessive wear on the tires.