BUYING TWO TIRES
While it's highly recommended that you change all your tires at once, it may not always be possible. However, even replacing just two of your tires can make a big difference - that is, if they're installed on a certain axle.
Where should you install the two new tires?
The new pair of tires should be placed on your car’s rear axle and the worn tires moved to the front. This makes for safer driving.
Why is it safer to install new tires on the rear axle?
Maintaining control of your car, particularly on wet roads, is easier with new tires on the rear axle. New tires have deeper tread, better grip, and evacuate water more effectively. Deeper tire tread keeps your car more stable on wet surfaces, especially during emergency handling, and helps prevent hydroplaning.
Does your car’s drivetrain matter when replacing two tires?
No, regardless of drivetrain, if you buy two new tires they should still be installed on the rear axle.
Should you regularly rotate tires if you only buy two of them new?
If the difference in tread depth between all four tires is 3/32' or less, then yes. Any difference in tire tread depth above 3/32' and the new tires should remain on the rear axle.