Yes, yet another oil question for the board.... sorry. Anyway, as temps are heating up, I'm curious if i can add 10W-30 as the Beast needs it, even though the engine has only seen 5W-30 since it was new last summer. I currently have 6K miles, and have not yet had my first oil change. I've added 3 quarts of Mobil One 5W-30 since the car was new.
I would probably stick with 5W-30, except I'm moving to Austin in a few weeks where summer temps will be equivalent to the surface of the sun.
I don't want to re-open the whole 5W vs. 10W debate, I just want to know if there's any problem with mixing different weights before the first oil change. I wouldn't think there would be. Thanks for any input guys.
Stick with the 5w-30 as your engine is used to it and it is what the car requires. BMW has done the proper testing for the car so I would think that they tested 5w-30 in extreme heat conditions before clearing it for use.
Adding 10w-30 weight oil to your car will not provide any more summer protection than staying with 5w-30 oil that is already in the crank. While viscosity breakdown was a valid concern years ago with mineral oils this is not necessarily true with a blended synthetic.
It is a standard practice with aviation fleet maintenance to change oil on condition, not according to time events. Of course this involves testing of the oil to validate the oiling properties still exist and to check contaminate levels. In most cases I have found that we change the oil because of contamination problems before we reach a state that the oil does not comply with the physical properties of a given spec. While you and I may feel that the oil needs changing sooner, BMW developed their recommended oil change cycle based on these same facts.
Personally I intend to change my oil more frequently but left to the their computer program most cars will achieve 15000 to 18000 miles before the light goes red. BMW could only develop such a position and assure their liability for this recommendation by evaluating the affects of high mileage on crank case oil conditions and here in Germany the recommended oil is the 10w-60 synthetic.
My car was a 6/2000 build and it has the 5W30 sticker, but being a Texas car I feel that the 10W60 is better during the summer months and certainly believe it is better if you track the car at all. As far as I know, both grades are approved by BMW for use in the S62 engine.
I may have misunderstood your post, I was not advocating mixing different grades of oil together at the same time (if you are in a pinch however, and don't have a choice, it would be better to do this than run the car for very long too low). However, if you want better summertime protection in the hot temps, I think the 10W60 is a better choice.