The ornamental design for a tire tread, as shown and described.
FIG. 1 is a perspective view of a tire tread showing our new design, it being understood that the tread pattern repeats circumferentially throughout the outer circumference and shoulder of the tire, the opposite side perspective being identical thereto;
FIG. 2 is a front elevation view thereof;
FIG. 3 is a side elevation view of the right side thereof; and,
FIG. 4 is a side elevation view of the left side thereof.
In the drawings, the dark stippled surface shading represents the recessed groove portions of the tire tread having a depth as best illustrated along the top and bottom edges of FIG. 2. The broken line showing of the sidewall, inner bead, and tire time are included for the purpose of illustrating portions of the “article” and forms no part of the claimed design.