Sorry I didnt' reply sooner. I don't get notifications anymore from this site. I've had 3 struts replaced under warranty. This was when I was driving it a lot more than I do now. First time it was both rear struts. Then the second it was only the back left, or right. I don't remember. I'm finding now, that I'm experiencing the same sticking strut problem whenever I push the car a little bit. But I might drive it once a week now, so it just doesn't bother me enough to pay for a new strut now that I'm well out of my warranty. Try lubricating the shaft. I'm not sure exactly what type of lube to use, but give subaru a call and find out what they use. From what I remember, the strut issue I had stemmed from a lack of lubrication on one of the bushings.