[CT Boost]

I run Motul X-cess exclusively.
Since I'm no longer stock and my other vehicle commands it, I run the 5w40 for a little extra protection and cause I buy it in bulk.
Other vehicle is a Porsche (flat 6).

From my understanding the go-to oils for the sti are the Motul X-cess and Shell Rotella.
Some people run the 5w30 of the X-cess as that exists too.

No experience with Liqui Moly on any of my vehicles.

I never understood that bs using Diesel engine oil.
many many people who modified there stis blew
Them up from 04-2010 while the GDs where still common. Probably 75% or more of them ran T6 - maybe it had something to do with that oil and how it reacted to a cold gasoline engine lol

 

[CT Boost]

Nothing wrong with a good diesel oil. It's stout oil and may have a rating or two more than required on a typical gasoline engine. That said, many of the oils I use don't have a "rating" for anything I use it in, but that just means they did not pay to get the rating in my case.

Not sure how a cold gasoline engine and diesel oil would be an issue when a diesel engine is going to stay cold all day long without a load on it. Subaru's motor failures aren't uncommon. I'd love to see the stats on how many short blocks are sold from Subaru (and aftermarket).

When it comes to a high load/heat motor and Motul, for me, it's 300v or bust. You select oil based on usage... There is no "best", there is just best for your usage (and metallurgy), which may require sampling to prove which is "best".

I just don’t think it’s smart. You don’t see anyone running diesel oils in 911s, and many of them are turbo boxers. My cold reference was to the heavy weight of the diesel oil, in winter time. I’d say it’s too thick.

 

[CT Boost]

Does anyone run the OEM idemitsu Subaru branded oil