The ornamental design for a tire tread, as shown and described.
FIG. 1 is a perspective view of a tire tread of this invention showing our new design, it being understood that the tread pattern repeats circumferentially throughout the outer circumference and shoulder of a tire, the opposite side perspective view being an inverted image thereto; and,
FIG. 2 is a full frontal elevation view of the tire tread thereof of FIG. 1.
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 edge of FIG. 2. The broken line disclosure of the tire sidewall and inner bead depicts environmental subject matter that forms no part of the claimed design.