Alternatively, you may want to have a mechanic check both the fluid and filter. Why is the fluid level wrong? If it's too high, someone added too much the last time the transmission was serviced. If it's too low, there's either a leak somewhere or the fluid is escaping through a faulty vacuum modulator (if so equipped). Have a mechanic inspect the transmission for leaks and check the vacuum modulator (again, if this vehicle has one)