Rotation is not alignment
Two services get confused more than any others in a tire shop, and the confusion costs people tires.
A rotation moves the tires to different positions on the vehicle, front to back and sometimes side to side. Each position wears a tire differently, so moving them around spreads the wear and makes a set last longer. It does nothing to the vehicle.
An alignment adjusts the vehicle itself: the angles at which the wheels meet the road. When those angles are off, every tire in that position wears unevenly, however often it is moved.
Here is the trap. A vehicle that is out of alignment and rotated regularly spreads the damage across all four tires instead of two. The wear looks even, because it has been shared out, and the owner concludes the tires simply wore out early. The cause was never found.
How to tell which you need
If the tires are wearing evenly across the tread and the vehicle drives straight, rotation on schedule is all it needs. If a tire shows more wear on one edge than the other, the steering wheel sits off center on a straight road, or the vehicle drifts to one side, that is alignment.
When you are not sure, ask for the alignment to be checked at the next rotation. The two jobs sit well together.
When else to align
Any time new tires go on, after a hard impact, and after work on the steering or suspension. A vibration rather than a pull is more often balancing, also done here. The national alignment page covers how the check works.
This is the Commercial & Consumer listing; the Phoenix city page explains the others.
About this store
The Phoenix store carries all nine Purcell tire categories and is managed by Patrick Taylor.
See the national car and light truck alignment page for all 40 locations.