Well, it's been 3,000 miles since my last oil change. So, the Check Oil Level comes up on the DIC. So I take it to the shop up the street since they'll top it off for free. Well, they tell me nothing registered on the dip stick. And I have a leak coming from the rear valve cover seal!! I didn't get an estimate but said I'd be back. He said call for an estimate. How much will this cost me? Also, how much is the gasket if I wanted to do it myself? On that note, is this a pretty easy gasket change??