The first number in a multi-grade oil is measured at -30C for a 5W oil and -35C for a 0W oil. But since it's a mid-SAPS oil, it has lower levels of some anti-wear additives and detergents than the other Motul oils to be more cat and DPF friendly. Although, it has a low TBN so I wouldn't push it much farther than 5k miles without ensuring that TBN retention is strong (uoa including TBN). It has a high HTHS and a thick viscosity at operating temp. Having said that, Motul X-Clean 5W-30 is a good choice. It is intended for cars that spec VW502, BMW Long Life 01, MB 229.1, 229.3, and 229.5 That's the same reason why German Castrol 0W-30 only meets API SL. They care more about the ACEA's specs and German builder approvals. Motul doesn't care about ensuring all of their oils meet the latest American Petroleum Institute specs. In a Subaru turbo, you should probably care more about HTHS than the grade on the bottle because HTHS is a better indicator of film strength. You do not want to run a 0W-20 in an STI ever, unless you're running something robust like Motul 300V 0W-20 or Red Line 0W-20, have a gauge to measure oil pressure, and spend way more than $30 on used oil analysis.
He also putts around Southern Florida in exotics and runs thin, expensive oil (Renewable Lubricants Inc.). The author is a plastic surgeon and some engineers there do not agree with all of the points in that article. The Motor Oil University (if that's what you're referring to) was not written by Bob or anyone that has formal training in the lubrication industry. The 0 grade will have lower viscosity after the car has been sitting at night and the 30 or 20 grade will have better flow at normal temps compared to the 40 grade (which isn't ideal for colder temps btw because of the high start up viscosity). So I found out I can run 0w-30 or even 0w-20 year round. A 0w-30 has a lower viscosity compared to a 5w-30 AT start up, but they both have the same flow rate at normal temps. The number before the W only determines how much the oil thickens after use. Higher grade oils have higher viscosity at start up temps which means less lubrication and longer time for the oil to get to temp. What is important is during start up, where most of the engine wear occurs. What changes in these scenarios (20 grade, 30 grade, 40 grade) is the oil pressure and the max flow rate also decreases as the grade goes up. Most oils will reach relatively the same viscosity at normal operating temperatures and at high temps only varying by a few units. Simply put, the grade relates to the viscosity of the oil at start up, driving conditions, and racing temps. This number is the 20, 30, 40.after the W.
Long story short, you always want to run the same grade oil that the manual says or even lower if you can. After reading his long "lecture" about oil and the common misunderstanding of the meaning behind the xW-xx labels on oil cans, I finally have my own answer of what I need to run in my STI. I finally said f*** it and went over to, which I felt was a little intimidating at first. Thank you guys for your response! Getting different feedback actually encouraged me to dig deeper and research more about engine oils. So please no comments on other brands.ĮDIT: Here are the tech sheets for these two oils I'm not looking to go to any other brand (I'm fine with the price). The options I'm looking at: 5w30 X-Clean, 5w30 Eco-nergy, or 5w40 X-cessĪre there any big difference between them? Which one do you use? Oil changes will also be done every 3000 miles regardless of which oil I'm going to use.
Which 8100 series oil should I use on my sti, w/76xxx, that's a DD, endures winters that reaches single digits? I plan on switching oil between the summer season (which I'll be doing a number of auto-x events) with the Motul 300V ester based oil and the winter/off season with an 8100 series oil.
I tried searching nasioc, here, and google but couldn't find a definitive answer. I could call them and get an answer but thought to get some other input and do some research on my own. The records, however, doesn't specify which 8100 series was used.
It says that they've used only Motul 8100 series oil ever since they started doing the maintenance. Hi guys, I recently bought my 07 sti and a shop in Santa Rosa, CA called FLI has done all of the upkeep and maintenance on this car.