The ornamental design for a tire tread, as shown and described.
FIG. 1 is a perspective view of the tire tread of my design;
FIG. 2 is a front elevation view of the tire tread of my design;
FIG. 3 is a side elevation view of the tire tread of my design;
FIG. 4 is a side elevation view of the tire tread of my design, taken from the opposite side of that shown in FIG. 3; and,
FIG. 5 is an enlarged, partial view of the tire tread of FIG. 1, as indicated by the break lines.
In the drawings, the broken line disclosure, including the broken lines defining the tread groove features and sidewall, depicts environmental subject matter and forms no part of the claimed design. The dash-dot-dot-dash lines represent the peripheral boundary of the claim. The claim is directed to the outer surface of the tire tread, as shown in solid lines and with surface shading.