The invention relates to a rubber tire composed of carbon black reinforced rubber carcass and having a rubber tread which is quantitatively reinforced with silica and contains a minor amount of carbon black reinforcement and/or carbon fibers. When said tread contains silica and carbon black reinforcement exclusive of carbon fibers, the said tread has a thin rubber layer over at least a portion of the outer surface tread intended to be ground-contacting wherein said rubber layer contains a combination of silica and/or carbon black reinforcement and carbon fibers. In one aspect, such alternative outer rubber layer (a) extends across at least a portion of the outer surface of the tread intended to be ground contacting and (b) contacts at least one other carbon black reinforced rubber component of the tire to provide a path of relatively low electrical resistance from said quantitatively silica reinforced tread to the bead portion of the tire carcass.