Abstract: A rubber composition based on at least an elastomer matrix, a carbon black, a silica, a silane coupling agent and short fibers, wherein the amount in phr of the silica is higher than that of the carbon black, wherein the amount of the silane coupling agent is more than 0.0% and less than 5.0% by weight per 100% by weight of the silica, wherein the amount of the short fibers is more than 0.0 phr and less than 5.0 phr and wherein the number-average length of the short fibers is less than 10 mm.

Abstract: A tire comprises at least one internal rubber composition having improved cracking resistance, the said internal composition comprising at least 50 to 100 phr of an isoprene elastomer such as natural rubber; optionally, 0 to 50 phr of another diene elastomer such as BR or SBR; 0 to less than 15 phr of a carbon black; between 40 and 100 phr of a nanoscale inorganic filler such as silica. The internal composition is free from or comprises less than 2%, expressed relative to the weight of the nanoscale inorganic filler of (elastomer/inorganic filler) coupling agent.