5w-20 Oil

[1stToyota]

Originally Posted by SilverGlow

You have the same confusion (misunderstanding) that many have in regards to 0w-20 and 5w20.

The fact is, the ONLY difference is that the 0w protects better during very cold weather during start ups. As to operational oil temperatures (180f to 212f and above) the 5w and 0w both protect the same because they are both 20 weight on the high end of the viscosity range.

So at hot operational temperatures, 0w-20 and 5w-20 provide the same protection.

If that is so, that they offer the same protection, then why does Toyota's TSB absolutely refuse to list "0w-20" as a suitable viscosity for the Yaris engine, yet they have no problem with saying that "5w-20" IS okay for our Yaris? And before you say it's okay because Amsoil says it's okay, when Toyota says not okay, remember that Amsoil does NOT offer an API approved 0w-20...you'd have to go the XL 5w-20 or XL 5w-30 to get an API approved oil to keep from voiding warranties.