The ornamental design for a tire tread, as shown and described.
FIG. 1 is a perspective view of tire tread in accordance with the present disclosure;
FIG. 2 is a front view thereof;
FIG. 3 is a side view thereof; and,
FIG. 4 is an enlarged fragmentary view thereof.
It should be understood that the pattern repeats uniformly throughout the circumference of the tread. Each side of the tire as shown in FIG. 3 is a mirror image of the other side. The lines defining the sidewall, inner bead, and the peripheral boundary between the tire tread and the sidewall depict environmental subject matter only and form no part of the claimed design.