The ornamental design for a tire tread, as shown and described.
FIG. 1 is a perspective view of a tire tread showing our design;
FIG. 2 is a front view thereof;
FIG. 3 is a top view thereof;
FIG. 4 is a right side view thereof;
FIG. 5 is a left side view thereof;
FIG. 6 is a fragmentary enlarged front view showing the details of the tread thereof;
FIG. 7 is a section view taken along line 7-7 in FIG. 6 thereof; and,
FIG. 8 is a section view taken along line 8-8 in FIG. 6 thereof.
The dot-dash-dot lines show a boundary between claimed and unclaimed subject matter, and thus form no part of the claimed design. The remaining broken lines are used to show unclaimed environment, and thus also form no part of the claimed design.