The ornamental design for a tire tread, as shown and described.
FIG. 1 is a front view of a full tire including the tire tread of the present application;
FIG. 2 is a perspective view thereof;
FIG. 3 is a side view thereof:
FIG. 4 is an enlarged, partial front view thereof;
FIG. 5 is an enlarged, perspective view thereof; and,
FIG. 6 is an enlarged side view thereof.
The broken lines and the region therebetween defining the inner bead and the sidewall depict subject matter that forms no part of the claimed tire tread design, and are included for the purpose of illustrating the full tire. Likewise, the tire interior forms no part of the claim. The tread pattern is understood to repeat throughout the circumference of the tire. The other side view is identical to the illustrated side view.