Groco GHSN13-12V Oil Change System. 12 volt. Sturdy bronze gear pump (up to 3. 5 GPH) delivers nearly twice the pumping capacity of competitive brands. Touch pad control enables you to empty or fill the oil pan of any connected engine. Pumps old oil out and fresh oil in with touch of a button. Built in controls prevent dry-run damage. 3 valves hook-ups.