I have 30K miles on my '05 6speed (G56). In the past it may have used maybe 1/2 a quart between oil changes. I use Valvoline premium blue and have changed the oil every 5,000 miles. I'm about to change my oil again at 30,000 miles and noticed that my oil level is down almost to the add mark, which according to the manual is almost two quarts low. Has anyone else had this much consumption in only 5k miles?