The ornamental Design for a tire tread, as shown and described.
FIG. 1 is a perspective view of a tire tread showing our new design, it being understood that the pattern repeats uniformly throughout the circumference of the tread;
FIG. 2 is an enlarged front elevational view thereof; and,
FIG. 3 is a reduced scale side elevational view thereof, the opposite side elevational view being a mirror image thereof.
In the drawings, the broken lines defining the sidewall and inner bead are for illustrative purposes only and form no part of the claimed design.