Thanks Bluesubie. I appreciate the advice. I looked at that when I ordered, and almost bought that instead. I went with the SS because of the raves it gets in various car forums. I might go OE direction next change.
Edit: when you say the SS doesn't meet specs, how so? Thanks.
Amsoil doesn't get it API or ILSAC certified. Not saying that it's not good oil, it just doesn't carry an API or ILSAC certification like XL and OE does.
It is recommended for
all domestic and foreign vehicles requiring any of the following performance specifications:
0W-20 (ASM): API SN (Resource Conserving), SM…; ILSAC GF-5, GF-4…;
From Amsoil's FAQ:
Why doesn’t AMSOIL license all of its synthetic motor oils?
Answer: If all AMSOIL motor oils were API licensed, the company could not source new raw materials from multiple suppliers, which would greatly increase the threat of supply disruption and the likelihood of extraordinarily high prices. To solve this problem, the API must establish base stock interchange guidelines for synthetic base stocks just as they have for other base stocks, as well as develop interchange guidelines for other components too. Furthermore, licensing formulas limits the ability to quickly adopt new technologies as they are discovered; each variation from the originally licensed formula requires re-submission for complete engine testing (see the Ask AMSOIL entry above for more information).