But it is bad for the environment. I think that is why 2 stroke engines are disappearing - they can't meet emissions regulations, no matter how thin the mix is. I say if you want clean oil, you should shorten the service interval and recycle the oil, not burn it and keep replenishing with new.

I've got a 2009 35d and its now got 17,000 miles on it ! Yes, periodically, I've needed to add a quart of oil. Its become less frequent now. Nothing to worry about.

grover432, I don't understand how the occasional addition of makeup oil to an engine is more damaging to the environment then an oil change.

Here in Massachusetts and other states in New England there are hundreds of thousands of waste oil heaters spewing unburnt hydrocarbons into the environment. These heaters are not very efficient and certainly do not have any sophisticated emmission controls.

Large trucking companies, refuse haulers, construction companies and a host of other fleet maintenance facilities actually resist longer drain intervals even though they have been proven to not only be safe and do not compromise engine life, so they can have used engine oil to heat their garages.

The math cannot work. Use a higher quality engine oil with a proactive condition monitoring program and add an occasional quart or even gallon of makeup oil and the overall consumption/environmental impact will trump the commonly practiced drain intervals used by those who are not open to such concepts as conservation, increased operational efficiencies and decreased consumption of limited resources.

I dont know the statistics offhand but I'm fairly confident that the quantity of oil that is actually recycled and put to good commercial use is miniscule when compared to the quantity of lubricating oil actually consumed in any given year. Recycling of engine oil is even more limited.

If 200 million cars on the road do the same thing, it adds up. Even though industry has a poor record and uses oil to heat their shops, etc., that just makes the argument for redoubling our efforts to put regulations in place to stop it.

I would say that most people considering the X35d are doing so because they want to pay less for fuel but still go fast. Many are also concerned about their carbon footprint.

There are many more non commercial drivers on the road than commercial trucks and the impact of good policy on reduced pollution whether through reduced fuel consumption, oil consumption or oil usage through extended service life can all play a part.

Maybe an extended oil change interval will result in increased engine wear and will require replacement earlier. I'm OK with that. If the engine needs a rebuild at 130,000 miles instead of 180,000 miles, maybe that is just the cost we have to pay.

In the mean time, if the X35d is supposed to burn oil, then so be it. If it isn't then BMW should fix it. Personally I don't like having to add oil, but if it is within BMW spec then I'd live with it. I certainly wouldn't call it a plus though because of new additives "propping up" the life of the existing oil when BMW says the interval they recommend is OK.