Mobil 1 0W40 vs 5W40

[julls]

Dear Bimmerforums,
I have seen a number of threads talk about this; but is there a general consensus on which of these oil type is better for E90? I have a 2006 model and I have been using mobil1 0W40 the last 60k miles. There are a few occasions where I had to top off (I have no oil leaks); some say this is normal. However mine happens occasionally but not always. Why? I'm I better off with 5W40? Would switching make any difference in terms of performance and/or gas milage?

Sincerely Yours.

[jclausen]

I'd run the 5w40, you don't need 0w40 out here

[julls]

I'd run the 5w40, you don't need 0w40 out here

Thanks. What makes 5W40 a better/recommended oil here in CA than 0W40? I'm curious. I had a friend bring his E90 (2011) to the same shop that's always changed my oil; he supplied 0W40 but they insisted on using 5W40. I thought that was odd because they always use my supplied 0W40.

[dankatz]

5W40 cured my wife’s GTI oil top off issue. If you are needing to top off try 5w40. That’s what our mechanic recommended doing for our VW.

[nashvillebill]

The Mobile 1 website says it doesn't have any oil that is certified for a 2006 330i. However, the Castrol Edge 5w40 is.

[jclausen]

Zero is winter viscosity rating meaning 0w40 40 would cover hotter temps and climates. But your not in a winter climate just like I'm not in one, but since the car has valve timing systems, the oil can't be to thick or a straight weight like older engines might run

[julls]

Zero is winter viscosity rating meaning 0w40 40 would cover hotter temps and climates. But your not in a winter climate just like I'm not in one, but since the car has valve timing systems, the oil can't be to thick or a straight weight like older engines might run

Thanks. I'll try the 5w40 at my next oil change. Does it matter if I use Castrol 5w40 or Mobil 1 5w40?

[julls]

The Mobile 1 website says it doesn't have any oil that is certified for a 2006 330i. However, the Castrol Edge 5w40 is.

Yes I believe BMW no longer recommends Mobil1 - because BMW claims it no longer meets it's Long-life rating. However, way back when, Mobil 0w40 was a recommended oil.

[julls]

I should also add that my car has now accrued 200k miles. Certainly one of the reasons I bring up this question is because my car is a high mileage vehicle and moving forward I'm looking to change my oil every 3k miles.