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 of the tire sidewall and inner bead depicts environmental subject matter. The dash-dot-dot-dash line, forming the peripheral boundary between the tire tread and sidewall, illustrates the bounds of the claimed design and forms no part thereof.