Looking at a car from the outside, it's easy to take for granted that all four wheels will stay pointed in roughly the same direction. But suspension systems -- particularly front suspensions -- are complex, and have to move in many different directions to do their jobs. Tie rods "tie" the wheel on one side of the car to the one on the other, ensuring that the suspension's job doesn't interfere with the wheels' ability to turn together.
Typically, the first sign that tie rod is bad or starting to fail is a shaky steering wheel. This happens because the steering wheel is beginning to lose control or "communication" with the wheels. As this starts to happen, the steering wheel will fight for control, resulting in shaking and vibrating. This can be increasingly noticeable when you try to turn the wheel.
The second sign that a tie rod is bad and at risk of breaking is a vibrating car. At this stage, the steering wheel has lost nearly all control over the wheels, and as a result, the tires will start to move involuntarily and shake on their own. You will feel this symptom more as you speed up, slow down or turn corners.
If the tie rods or tie rod ends have been worn out or damaged long or severely enough, they will affect how your tires wear. Worn tie rod ends will allow your tires to "toe out," or point away from each other while you are going in a straight line. This will cause the inside of the tire tread to wear faster than the outside.
