About 2 or 3 months ago I noticed my reservoir was a little low. So i dropped in some dot 3 brake fluid that had been sitting around for about a year or so, didnt think the stuff went bad. Now, as its been getting colder and colder, when i start it on a cold day and let the clutch out theres about an inch or so of play and slowly pressing it in you can feel the friction of the moving parts before its pushed so far it enguages. Once it warms up theres no problem, like new. Is there a way to purge all the old fluid out or perhaps a slave cylinder is wearing?? Its on a 99' 5 speed 6 banger. TY in advance