Tire with rubber tread containing precipitated silica and functionalized carbon nanotubes

A tire with a circumferential rubber tread of a rubber composition which comprises, based upon parts by weight per 100 parts by weight rubber (phr):

• (A) 100 phr of at least one diene-based elastomer,
• (B) rubber reinforcing filler comprised of precipitated silica, together with silica coupler for the precipitated silica having a moiety reactive with hydroxyl groups on the precipitated silica and another, different, moiety interactive with said diene-based elastomer(s),
• (C) about 0.5 to about 30 phr of carbon nanotubes having an average diameter in a range of from about 5 to about 20 nanometers and an L/D dimensional ratio in a range of from about 100 to about 1000;
• wherein said tread rubber composition contains less than 30 phr of rubber reinforcing carbon black, and
• wherein the carbon nanotubes are functionalized with a carbon nanotube coupler having moiety containing a pi electron network.