The ornamental design for a tread portion of an automobile tire, as shown and described.
FIG. 1 is a perspective view of a tread portion of an automobile tire according to a first embodiment of our design;
FIG. 2 is a front view thereof;
FIG. 3 is a top view thereof;
FIG. 4 is a right side view thereof;
FIG. 5 is a left side view thereof;
FIG. 6 is a rear view thereof;
FIG. 7 is a fragmentary enlarged front view showing details thereof; and
FIG. 8 is a section view taken along line 8-8 in FIG. 7;
FIG. 9 is a section view taken along the line 9-9 in FIG. 7; and,
FIG. 10 is a section view taken along the line 10-10 in FIG. 7 thereof.
In the drawings, the broken lines defining the sidewall, inner bead and the peripheral boundary between the claimed tire tread and the unclaimed sidewall depict environmental subject matter that forms no part of the claimed design.