I have a 2005 H2 SUT that is supercharged with a Magna supercharger. Now, I don't know that much about superchargers, but I know what they do ultimately. I have had an issue with the 6 liter engine making a noisy lifter rattling sound. So, I took it to a local mechanic recommended by the guy I bought the truck from. The mechanic told me the original owner had the wrong motor oil put in the H2. He said it needed synthetic motor oil since it had a supercharger, so he changed out the motor oil. It still does the same thing. I called magnacharger and sure enough, the super charger uses synthetic oil and it holds about 6-8 ounces and is good for 99,000 miles. Magnacharger could care less what kind of motor oil you run in the truck. So, has anyone had this lifter rattle? What kind of motor oil (brand and viscosity) do you use. I live in a far north state (cold). Any other ideas orsuggestions???