I've been a long time lurker on here, but I couldn't find an answer to this by doing a search.
I drive a mildly modified 2005 Subaru Forester XT. By mildly modified, I mean that I have installed a large turbo (TD05-18g) that is advertised as a 400hp (at the crank) turbo. This car is a daily driver, and I like to do a full throttle pull when it's safe to, which isn't very often. Maybe a few times a week, if I'm lucky.
My main concern regarding oil is about change intervals, and the fact that the turbo is an older aftermarket turbo that has no water cooling.
Based on other people's UOAs, and other oil recommendation threads on here, I decided to run Rotella T6 5w40. The part that confuses me is how often do I need to change it? Does UOA tell the whole story as far as the bearing section of my turbo is concerned? I have been running very short OCI's (~3000 miles) because of the oil-only-cooled center section of the turbo. Is there some way of knowing throw oil analysis whether the oil is cooked, and more prone to leaving deposits in the turbo?
According to the Kublin method of determining OCI, I should be changing my oil every 3000 miles, but this is based partly on engine output, of which I don't normally use daily. I have used the calculator on this page:
http://neptune.spacebears.com/cars/stories/interval.html
I usually take it very easy during the last 2 minutes of my drive home, before I shut the engine down. My gut tells me that it should be safe to run this oil to 6000 miles and beyond, but I wonder how I can know that this is safe?
I drive a mildly modified 2005 Subaru Forester XT. By mildly modified, I mean that I have installed a large turbo (TD05-18g) that is advertised as a 400hp (at the crank) turbo. This car is a daily driver, and I like to do a full throttle pull when it's safe to, which isn't very often. Maybe a few times a week, if I'm lucky.
My main concern regarding oil is about change intervals, and the fact that the turbo is an older aftermarket turbo that has no water cooling.
Based on other people's UOAs, and other oil recommendation threads on here, I decided to run Rotella T6 5w40. The part that confuses me is how often do I need to change it? Does UOA tell the whole story as far as the bearing section of my turbo is concerned? I have been running very short OCI's (~3000 miles) because of the oil-only-cooled center section of the turbo. Is there some way of knowing throw oil analysis whether the oil is cooked, and more prone to leaving deposits in the turbo?
According to the Kublin method of determining OCI, I should be changing my oil every 3000 miles, but this is based partly on engine output, of which I don't normally use daily. I have used the calculator on this page:
http://neptune.spacebears.com/cars/stories/interval.html
I usually take it very easy during the last 2 minutes of my drive home, before I shut the engine down. My gut tells me that it should be safe to run this oil to 6000 miles and beyond, but I wonder how I can know that this is safe?