I just got 08 Impreza Outback Sport, but when I was in Japan, I drove 96 BG5 Legacy GT wagon Twin-Turbo model and I was changing oil with aftermarket brands.... but one day, I went to Subaru dealership and changed oil there. The difference was so obvious (that Legacy had 50,000 miles or so and city traffic mileage) the engine run so smooth after I changed the oil there.

 

Subaru Japan released the oil named "Les Pｌeiades"(sorry if the spelling wrong) and they made it with ELF brand. 100% Synthetic！！！

http://www.elf-lub.jp/pro/subaru.html

Someone had mentioned in this thread that synthetic oils are thinner than conventionals, which is also exactly the opposite of the truth, interestingly enough. The primary base oil in a 'conventional' multigrade oil of a given viscosity (let's say 5W30 for example) is actually noticeably thinner than the primary base oil in a genuine PAO 'synthetic,' but the 'conventional' then uses a load of viscosity-index improvers to make it thicken as it warms up.

 

 

I'm sure you're correct about respective weights of the base oils.

All I meant when I said "thinner" was that _at normal room temperature_, a synthetic oil of the same LABEL viscosity will pour noticably easier and appear less viscous than dino oil of the same weight. You don't have to have much of an imagination to see how this could dramatically accellerate leakage on a car with seal issues.

 

Nathan

Sorry, wrong thread; Post deleted.

[...]Subaru Japan released the oil named "Les Preiades"(sorry if the spelling wrong) [...]

A not-surprising labeling: http://en.wikipedia.org/wiki/Pleiades_(star_cluster)