The ornamental design for a tire tread, as shown and described.
FIG. 1 is a perspective view of the tire tread showing our design;
FIG. 2 is a front view thereof;
FIG. 3 is a rear view thereof;
FIG. 4 is a right side view thereof;
FIG. 5 is a left side view thereof;
FIG. 6 is an enlarged detail view thereof; and,
FIG. 7 is an enlarged cross-sectional view thereof, taken along line 7-7 in FIG. 6.
The dash-dash broken lines are used to show portions of the tire tread that are not being claimed, and thus form no part of the claimed design. The dash-dot-dash broken lines are used to show the boundary between unclaimed and claimed subject matter, and thus form no part of the claimed design.