I have an 08 4.8i with 142k miles and due for an oil change. I've used the traditional 5w30 and 0w40 in the past, but something tells me at this mileage it's too thin to use. What are you guys using in your 4.8's? I have read posts of people using the 10w60 with no issues. I also do have the valve stem seal issue that has started to get pretty bad in last 3k miles or so