The ornamental design for a tire tread, as shown and described.
FIG. 1 is a perspective view of a full tire including the tire tread of the present application;
FIG. 2 is side view thereof;
FIG. 3 is a partial, enlarged front view thereof; and,
FIG. 4 is a partial, enlarged side view thereof.
The remaining portions of the tire partially shown in FIGS. 3 and 4 are a repetition of the illustrated portions, and the other side of the tire is identical. The remaining portion of the tire partially shown in FIG. 4 is a repetition of the illustrated portion. The broken line showings are included for the purpose of illustrating environment and form no part of the claim, specifically the innermost broken line represents the inner bead, the intermediate broken line represents a surface contour change along the sidewall between the inner bead and the tire tread, and the outer broken line represents the edge of the sidewall adjacent the claimed tread shown in solid lines.