I have a 2011 Silverado 4.3L. Im slowly leaking oil, appears to be near the timing chain cover. When I noticed it I was below the low line on the dipstick. Have not seen any oil drips on my driveway but if you look around the timing chain cover and oil pan there is always a thin layer of oil. Ive had to add a quart of oil two weeks after topping it off. But there has been zero drips?!?! Can't figure out where it's going... Has anyone else had this issue? (Parked in the same spot on a clean driveway when parking and checking the oil level)