Rubber composition and pneumatic tire with tread

The present invention is directed to a rubber composition comprising at least one diene based rubber; a sulfur donor; a sulfenamide accelerator; and a dithiophosphate of the formula wherein Q is divalent Zn or S, and Rmay be identical or different, and Ris hydrogen or a monovalent hydrocarbon group of 1 to 18 carbon atoms; and wherein the zinc content of the rubber composition is less than 0.5 parts by weight, per 100 parts by weight of elastomer (phr) as Zn metal. [0002] The rubber composition may be used in a tread of a tire.