The ornamental design for a tread for a tire, as shown and described.
FIG. 1 is a perspective view of a tread for a tire showing my new design,
it being understood that the tread pattern is repeated throughout the
circumference of the tread for a tire; and,
FIG. 2 is an elevational view of the tire tread design shown in FIG. 1.
The broken lines defining the tire inner bead and sidewall are for
illustrative purposes only and form no part of the claimed design.