Amsoil told me that Amsoil is fully compatible with Mobil 1 and its not a problem. Would I do it? No, maybe only for a short interval. If Amsoil uses ExxonMobil PAO then I can see why they are compatible.
quote: Originally posted by buster: Amsoil told me that Amsoil is fully compatible with Mobil 1 and its not a problem. Would I do it? No, maybe only for a short interval. If Amsoil uses ExxonMobil PAO then I can see why they are compatible.
ExxonMobil makes many pao's Each one has characteristics different from the other. Who ever said the pao basestock in mobil 1 5w30 is the same as in Amsoil's 5w30? Mobil probably makes very expensive basestocks for other applications other than street automobiles but that doesn't mean thay are going to use them in street oil. I wouldn't if I was marketing for a conventional oil change schedule, it would just price them higher than the competition and cost sales.
This was taken directly from Mobil's website in the "myths about synthetic" section:
Q: You can't mix Mobil 1 with conventional oil.
A: Mobil 1 with SuperSyn™ is fully compatible with conventional motor oils, semi-synthetic motor oils and other synthetic motor oils should it be necessary to mix them. But the superior performance of Mobil 1 with SuperSyn™ will be reduced by diluting it.