The Generac 6840 maintenance kit is designed for the 5500-8000 watt portable generators. If your generator has been running for extended periods or has been stored for several months, it's a good idea to change the oil and fill the tank with fresh gasoline. Be sure to review your owner's manual for the suggested maintenance schedule. Tune-up kit keeps your generator running at optimum performance. Scheduled maintenance is a necessity to ensure the long life and top performance of your portable generator.