I hope this helps you:
Straight from the M3 forum....
-The oil change monitor doesn't evaluate the actual oil life remaining, it just uses the amount of fuel used, engine temps metrics etc. The Condition Based Service (CBS) interval is not sophisticated enough/reliable.
-The Maintenance intervals proposed by BMW will get your car through warranty period, but after that get ready for massive repair $$$.
-BMW went to extended (15k) intervals based on the oil change monitor only when and because they started paying for maintenance. The intervals are only that long because BMW wanted to save money/they are paying for it
Is there one shred of evidence for any of the three above "facts"? People routinely say this stuff on every bmw forum I've been on, yet it's all theory and speculation. Not only that but it is weak theory and weak speculation.
Consider:
-Thousands of people have been using the normal CBS for years, and you don't see BMW engines grenading very often. Many times more people stick to the CBS than those that don't. Thousands of people have gone 100k+ miles on the CBS intervals as they have been used for many years.
-The CPO program would be an utter disaster if the oil change intervals were too long, as these more used BMWs would show lots of signs of engine trouble and cost BMW $$$ in CPO repairs.
-BMW's around the world come with the SAME CBS oil life system- and yet the USA is one of the ONLY countries in the world where maintenance is covered. You really think BMW would threaten their worldwide reputation, engine reliability and CPO programs in every country in the world, just because maintenance is covered in the USA for four years?
-The condition based service does measure oil quality- at least at some level. Please look at the pdf file on post #3 for some evidence.
http://forums.bimmerforums.com/forum...d.php?t=954499
-BMW is not the only manufacturer to rely on CBS, porsche, mercedes and others do it too.