I have a 2008 Subaru STI with EJ257 (daily driver, stock). There are a number of oils that have tried true (by UOA) for these engines that I've seen here and other forums. Right now I'm running GTX 5W30 for 3250 mile OCI (warranty recommended) but am interesting in trying some of these other EJ257 proven oils. I'm not sure if I want to go with a longer OCI now, but that's not really the point of this post.
I'm interested in running some of these EJ257 'proven' different oils/brands and then figuring out what's best for the long run.
Is there a good method to figure this out? Should I run different weights in a specific order (5W30; 0W30; 5W40)? Kind of like doing a wine tasting or flight where it's OK to go from a lighter white to a heavier red or dessert, but not usually the other way around.
How long do I run an oil to get an UOA that is meaningful? Does any trace mixing of one with the other (such as following a Rotella T 5W40 fill with a GC 0W30 fill) affect the UOA?
Would I/should I do two or more OCIs with the same oil before getting a UOA?
I'm asking more out of general larger concept and to see opinion. I may go through the same process with the family car. I'm anticipating that the answer to my questions is that it really doesn't matter which I use first or second and I shouldn't be concerned about any mixing.
I've always been a guy that has stuck to one brand/viscosity for a given vehicle. I've never seen any oil related problems in one of my cars, and must say, typically get rid of the car before 125K-150K miles.
For some reason (
reading these forums), I'm considering to apply some method or logic to my choice.
Or...maybe I'm overthinking all this and should just pick one (like Rotella T 5W40 - it's cheap, easily available, has decent four seasons viscosity, and seems to be Subaru turbo boxer friendly), not care about UOAs, and worry about other things.
I'm interested in running some of these EJ257 'proven' different oils/brands and then figuring out what's best for the long run.
Is there a good method to figure this out? Should I run different weights in a specific order (5W30; 0W30; 5W40)? Kind of like doing a wine tasting or flight where it's OK to go from a lighter white to a heavier red or dessert, but not usually the other way around.
How long do I run an oil to get an UOA that is meaningful? Does any trace mixing of one with the other (such as following a Rotella T 5W40 fill with a GC 0W30 fill) affect the UOA?
Would I/should I do two or more OCIs with the same oil before getting a UOA?
I'm asking more out of general larger concept and to see opinion. I may go through the same process with the family car. I'm anticipating that the answer to my questions is that it really doesn't matter which I use first or second and I shouldn't be concerned about any mixing.
I've always been a guy that has stuck to one brand/viscosity for a given vehicle. I've never seen any oil related problems in one of my cars, and must say, typically get rid of the car before 125K-150K miles.
For some reason (
Or...maybe I'm overthinking all this and should just pick one (like Rotella T 5W40 - it's cheap, easily available, has decent four seasons viscosity, and seems to be Subaru turbo boxer friendly), not care about UOAs, and worry about other things.
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