I have a scion xb and i just had my 3rd oil change at an econolube, and i always have told them to use 5w30 oil in my car, but this time i just decided to ask the man at the desk "what types of oil do you have here?" and he responded w/ "we use a synthetic blend bulk oil in all our cars and it is a 10w30 oil."
So needless to say now im freaking out, cause i knew it should have 5w30, the guy says it's really no big deal, but i don't trust him
so...my question to you is

1. Is it really that big of an issue, and if i next time mix it with 5w30 will it cause problems?
2. Is a "synthetic blend' okay for scion XB
?

save a couple of bucks and do it your self...

1. Is it really that big of an issue, and if i next time mix it with 5w30 will it cause problems?
2. Is a "synthetic blend' okay for scion XB
?

1. Your engine is going to work harder at start up becasue it is a thicker (10W) oil that what is recommended (5W). Since start up is when the most amount of wear occurs, I would only use a 5W or 0W weight oil. You will hear some say its no big deal, and it may or may not be, but tolerances in modern engines are much tighter than older models. I just dont feel comfortable with a 10W. Oil is cheap. New engines are not.


2. Full syns, syn blends and dino oil are all fine for this engine. I run full syn myself, but all 3 will be fine.