Wow, very interesting find!
Quote:
Originally Posted by m6pwr
Th N55 does have a different and, BMW says, improved ccv system that should do a better job of separating or removing oily vapors before the air is sent on to the intake tract.
There are a couple other things that could mitigate intake deposits -
I think the current f30 n55 does a better job of controlling oil temps and keeping oil temps down, particularly when you start to "exercise" the engine.
BMW will be switching to Shell as its lubricant partner starting in 2015. One reason for the switch may be (and I'm guessing) is that Shell is way, way ahead of other oil companies in refining "gas-to-liquid" lubricants. These GTL lubes made from natural gas are very clean and have low deposition rates, and more to the point, have very low volatility (less oily vapors) compared to more conventional synthetics.
Finally, there was a thread on the BITOG oil forum about intake deposits and Doug Hillary (a very experienced lubricants engineer who has worked for Castrol and Exxon/Mobil) made this observation: "As for OCIs - I recommend following the Warranty requirements to the letter! When in Germany this year I was given some data from very reliable sources that suggests that shortening the OCIs and/or using non-Approved lubricants may affect intake deposits in a negative way." What he is saying is that the most deposition from an oil occurs when it is new or fresh. So, more frequent oil changes just feed or replenish deposits and accelerate intake deposits. Just one more reason to avoid unnecessary frequent oil changes. Stick to BMW's recommended oil change interval. Here's the thread http://www.bobistheoilguy.com/forums...72#Post2082572 |