Last year when I skied Leatherman I took my 2wd Toyota Matrix to just past where the road splits between the West and East Forks of the Pahsimeroi. It's the West Fork road (right turn) that goes to the Leatherman trailhead. There is some kind of igneous dike that cuts across the road just past the split that causes it to get rather steep and rocky. I parked there and rode my bike to the trailhead. It's a pleasant bike ride that doesn't take too long because there isn't too much vertical gain. Probably on the bike by 6 am and at the trailhead 45 minutes later. And that was with a heavy load (skis, boots, etc.).
I bottomed out several times with my Matrix and probably will never do it again. Glad I did it once, but it's really not a road for low clearance cars.
Last weekend I had a 4 x 4 and took it to the first muddy corner on a hill beyond the split. See my trip report for how I got stuck in a mudhole there, and how there is a detour around this section of road. I parked the truck at this point and biked to the trailhead. A 2wd van made it to this same point, so I imagine your Forester could get there. It's a just a matter of zigging and zagging around boulders, and how many time you want to bottom out. There is no mud before the place I got stuck, so you don't have to worry about that.
The road is certainly quite good to Horseheaven Pass, so you could always stop there and hike up Cayuse Canyon to Doublesprings Peak. It's no Leatherman, but still a great hike.
Jim
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