The ornamental design for a tire tread, as shown and described.
FIG. 1 is a perspective view of a full tire including the tire tread of the present application;
FIG. 2 is a partial side view thereof;
FIG. 3 is a front view thereof; and,
FIG. 4 is a partial front view thereof.
The side view of the inner and outer sides of the tire are the same, i.e., the tire tread is symmetrical. Further, the remaining three-fourths portion of the side view of the tire is repetitive of the illustrated one-fourth portion. The broken line showings of the sidewall, inner bead, shoulder tread, and the peripheral boundary between the tire tread and the sidewall are included for the purpose of illustrating environment and form no part of the claim.