When a car's tires are rotated, the tires on the drive wheels should be moved to the non-powered axle, while the other tires are swapped left-to-right and installed on the drive wheels. This helps distribute the wear evenly across the tires, preventing a loss of traction.
In addition to the standard tire rotation pattern, tires may be rotated in an X pattern whether the car is front or rear wheel drive. The front passenger tire is swapped with the rear driver's tire, and the rear passenger tire replaces the front driver's tire.
Some tires are directional, meaning they are specially designed to go on either the right or left side of the vehicle. In this case, the front and rear tires on each side of the vehicle are simply swapped. If a vehicle has tires of different sizes on the front and rear axle, then the tires can be swapped left to right.
If a car has a full-sized spare tire, it should periodically be swapped out for one of the wheels on the non-powered axle. This ensures that the spare wears at a rate even with the other tires. Replacing a worn tire with a brand-new spare may cause a car to ride unevenly.