Debuting as the B9 Tribeca at the 2005 North American International Auto Show, the sole generation of the Subaru Tribeca (WX code) served as the brand's flagship mid-size crossover. Offering 5- and 7-passenger seating configurations, its initial styling crafted by Andreas Zapatinas featured a polarized aerospace-inspired front grille design. Mechanical hardware centered around the 3.0-liter EZ30D flat-six engine (245 hp) paired with a 5-speed automatic and VTD All-Wheel Drive. The engineering setup effectively combined the low center of gravity inherent to the horizontally-opposed engine layout with a rigid chassis frame, delivering precise handling and composure across dry pavement and slippery surfaces alike. Engine bay packaging ensured optimal front-to-rear axle weight distribution alongside efficient thermal cooling under sustained driving loads.

A major 2007 facelift dropped the 'B9' moniker, adopting a conservative front-end appearance alongside a larger 3.6-liter EZ36 flat-six engine (256 hp) optimized for regular unleaded fuel. Manufactured exclusively at the Subaru of Indiana Automotive plant, Tribeca production wrapped up in January 2014. Designers placed a strong emphasis on cabin ergonomics, occupant visibility, and long-distance driving comfort. Robust mechanical reliability across the drivetrain and suspension components helped establish this generation as a benchmark choice within its competitive market segment worldwide.