sorry to tell you this, but, i've seen a very consistent trend with 850 transmissions. if you flush them, they will die sooner! i know it sounds weird, but it's just what i've seen. think of it like this. when the plates grind down in the trans. they shed off metal particles, which although very small, are actually filling in the holes in the plates. they actually act like a buffer between the moving parts. this might all sound like science fiction, but i've talked to three volvo tech. friends of mine that all say the same thing. anyway, i wish you luck with it, and please don't flush it!!