The ornamental design for a tire tread, as shown and described.
FIG. 1 is a front angled perspective view of a tire tread, it being understood that the tread pattern is repeated throughout the circumference of the tire tread.
FIG. 2 is a front elevational view of the tire tread, it being understood that the tread pattern is repeated throughout the circumference of the tire tread, the opposite view being the same as that shown.
FIG. 3 is a flat pattern view of a portion of the tire tread, it being understood that the tread pattern is repeated throughout the circumference of the tire tread; and,
FIG. 4 is a sectional view taken through line 4--4 in FIG. 3.
The broken line showing of portions of the tire tread, the sidewall, peripheral boundary between the claimed tread and the sidewall, and the inner bead are for the purpose of illustrating environment that forms no part of the claim.