Any mod that you could make to a 4th Gen Legacy (2004-2009) would apply to your OBXT. The 3rd Gen OBes are built on the 4th Gen Legacy platform (read: essentially the same platform) and have extended suspension mounts to raise the body for OB ground clearance, smaller brakes, larger tires, different final drive ration, and slower steering rack ratio. But the mechanicals, engine, turbo, cooling, AWD setup, etc. are the same.
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