[wiswind]

In short, whenever you replace a tie rod end, a alignment must be done in order to have the front tires running in parallel with each other.
The tie rod is adjusted to determine the angle of the tire......front in/out relative to the rear of the tire.
Not a good explaination......but the tie rod is a steering component, when you turn the steering wheel, it is what turns the tires.
So, as 12ounce is pointing out........you set your steering wheel so that your vehicle is pointing straight ahead......and adust the tie rod so that both tires are pointing STRAIGHT ahead.
As you adjust 1 tie rod......it is turning the tire SLIGHTLY left or right....while the other side is NOT turning.
Point being....you want the front tires tracking exactly together.....or you will wear out your tires.