GOING FOR THE GM JUGULAR; Latest Scion models provide yet another weapon in Toyota's push to the top of the world's automotive ranks.(News)

Byline: BOB GRITZINGER

Toyota's latest swing at staying relevant to the 30-and-under set-and another key to taking the title of "world's largest automaker'' from General Motors-arrived at the Chicago auto show in the form of the 2008 Scion xB and the 2008 Scion xD.

The second-generation xB loses some of its boxy styling, taking on some of the design cues revealed in the t2B concept shown at the 2005 New York show. The xD, although touted as an all-new vehicle for Scion, is a replacement for the xA hatchback in the Toyota youth-niche lineup.

The xB loses its sharp corners and grows by more than a foot in length and 3 inches in width, while decreasing 1 inch in height. The wheelbase is wider and brakes are larger on the new model.

Under the hood, the xB gets the Scion tC's 2.4-liter, 158-hp, 162-lb-ft four-cylinder engine, linked to either a five-speed manual gearbox or a four-speed automatic. The engine gives the xB a 55-hp increase in power over the previous model's 1.5-liter four. The xB goes on sale in April.

Meanwhile, the five-door hatchback xD arrives in August, filling the gap left in the Scion lineup when the xA ceased production in late 2006 (the company did not offer a 2007 model). The xD, which shares its chassis with the Toyota Yaris, is ...