Depends on what you mean by old. The older the oil gets the more acids it accumulates which can erode bearings. If you last changed it within 1,000 or so miles I wouldn't bother changing it before storing it. If you do change it before storing it, I wouldn't bother changing it before driving 2000 miles after taking it out of storage. i.e if you change the oil every 3000 miles like you should, just continue changing it based on mileage and ignore the months of non-use.