DETROIT – As part of its move to value pricing, General Motors will increase bumper-to-bumper warranty coverage on all 2006 Buick vehicles from three years or 36,000 miles to four years or 50,000 miles, according to Automotive News. Buick Marketing General Manager Steve Shannon told Automotive News that GM wants to add value without increasing prices. Shannon said GM will make OnStar standard on all models beginning in 2006. And it will offer roadside assistance and courtesy transportation when vehicles remain in the shop overnight, Shannon said in the Automotive News interview.