Tire with tread rubber composition which contains dual silica moieties

A method of preparation of a precipitated silica reinforced rubber composition for a tire tread which contains dual silica moieties comprised of an in situ hydrophobated precipitated silica and a hydrophilic precipitated silica comprised of at least two sequential preparatory non-productive mixing steps followed by a productive mixing step, which comprises, based upon parts by weight per 100 parts by weight rubber (phr):

• (A) blending a hydrophilic precipitated silica with a rubber composition comprised of at least one conjugated diene-based elastomer in at least one preparatory non-productive mixing step in an internal rubber mixer, and hydrophobtaining said hydrophilic precipitated silica with a hydrophobtaining agent in situ within said rubber composition in at least one of said non-productive mixing steps to thereby form a hydrophobated precipitated silica-containing rubber composition (at a temperature of, for example, in a range of from about 135° C. to about 175° C.);
• (B) removing said hydrophobated precipitated silica-containing rubber composition from its internal rubber mixer,
• (C) blending a hydrophilic additional precipitated silica with said hydrophobated precipitated silica-containing rubber composition in at least one different and subsequent preparatory non-productive mixing step in an internal rubber mixer, to form a rubber composition which contains dual silica moieties in a form of a combination of said in situ hydrophobated precipitated silica and said hydrophilic additional precipitated silica;
• wherein said hydrophobated precipitated silica is hydrophobated in situ within the rubber composition by treatment with an organoalkoxysilyl polysulfide or organomercaptosilane which optionally includes an alkoxysilane.