I've got a great PDF on oil that covers just about anything you would want to know. Everything from bypass filters to technical specs to brand comparison charts (wear rating, ect.) It was last updated in 2003, so it is a few years old. Unfortunately, the online link no longer works and I can't upload it because of it's size, 3 MB, 177 pages. So, if anyone is interested shoot me a pm and I will get it to you. I'm not advertising anything, just trying to spread some excellent information, especially those new to oil. :)