Pneumatic radial tires for passenger cars or light trucks traveling on rough roads

摘要

PROBLEM TO BE SOLVED: To keep the bottom of a groove unapt to be cut injured due to a foreign matter such as a stone by providing at least grooves extending in the circumferential direction or substantially in the circumferential direction, and steep inclined grooves extending in the inclined direction with small angle against the circumferential direction. SOLUTION: The tread of this tire is provided with three circumferential direction grooves 1 extending in the circumferential direction, many steep inclined grooves 2 extending in the inclined direction with a relative small angle such as 8 degees against the circumferential direction, and many gentle inclined grooves 3 extending in the inclined direction with relative large angles against the circumferential direction. In at least a part territory of the steep inclined groove, the bottom up of the groove is executed so that the groove depth 3.0 mm becomes 30.3%, of the groove depth (9.9 mm) of the circumferential direction groove, a thin groove 4 extending from the groove bottom further extending inward in the radial direction is provided, the groove width of the thin groove 4 is 1.2 mm, and the groove depth is formed to be 5 mm corresponding to 50.5% of the depth (9.9 mm) of the circumferential direction groove.