i went to walmart the other day. in the section of oil where mobil 1 was, they had mobil 1 0W-30 that says its the "green" oil because it gets better gas milage over the life of the engine. Also I've heard of people using 5W-30 in the winter. I dont know about that if my car says to always use 10W-30. what do you guys think about using the 0W-30 and the 5W-30? I live in southern michigan, winters usually get down just under zero on the peak coldest says.

I always use 5W-30 for all season. I don't have any problem with that. I follow what my owner book say. I'm not sure about 0W-30. I don't own 3800 engine. If your owner book say use 10W-30 then you should use it.

I wouldn't use 0-30. Don't buy into the hype of "green" because once the oil warms up it's 30 weight anyway. Plus it doesn't take long for the oil to come up to temp anyhow.

its for saving money but did you see you have to own your car for like 15yrs and use it as your daily oil to save like 400 not worth it plus less protection

The 0w30 IS a little better than the 5w30 in that its a little less viscous, however the difference is negligible. Google 0w30 and read amsoil's page.

If I lived way up north where it was pretty cold fall & winter. I would use it. I already use the Amsoil XL-7500.

http://www.synthetic-motor-oil-change-an...ct-code-tso.php

http://www.mobiloil.com/USA-English/MotorOil/Oils/Mobil_1_0W-30.aspx

Its a sell ploy. 0w-30's been out for a while and the bottle originally stated its a standard for new European cars. Since the term green is the in-thing, they slapped it on it because it is true, sorta.