We had a guy that worked for our company that didn't change the oil in his Chevy Trailblazer for over 40K miles (company car). No apparent damage as the vehicle now has over 80K miles and seems to run ok with no smoke or loss of power. I can't understand his thought process as the company pays for all maintenance. The TrailBlazers also have a large sump like the X5, about 7 qts, so I think that helped.

Although oil test companies have shown the oil viscosity to be fine at the recommended intervals I change mine at half the recommended intervals or at least yearly. My only reason is peace of mind. Oil is probably the most important component of the engine and the realitive low cost is good insurance. Actually the filter is probably more inportant as it is the particles in the oil that I would want to ensure are removed or kept to a minimum.

Based on the above I have had vehicles go to 350k km without buring a drop of oil between changes.

Also funny how BMW recommended intervals increased when maintenance became included.

Very useful maintenance thread from m3forum. Note the link for not sticking to BMW intervals.
e46 M3 Maintenance Thread - BMW M3 Forum.com (E30 M3 | E36 M3 | E46 M3 | E92 M3)

That's just another owners opinion. No new news or facts in that post to back up why he changes it at 7500 instead of 15k miles.

In the past I had a simple answer for this, but after requesting and reading the "Old school maintenance schedule" from the BMWCCA, I have sort of changed my mind. Unfortunately, I can't just post the plan here for a few reasons; 1) it is copyrighted and they ask you not to, 2) it is updated periodicially with changing info and 3) they have been very helpful in answering my tech related questions and I don't want to anger them. However, it doesn't say you can't discuss it. Short version from what I understand is if you are not planning on keeping your BMW long term (100k miles+) there is no reason to deviate from what BMW recommends. If you are planning on keeping it over 100k or out of warranty and use BMW's oil and filters, it seems like it wouldn't hurt to cut the 15,000 mile interval in half. All of this also depends on how and where you drive as well as other factors. There were a few pages on the topic of oil change intervals, the differences between oils, oil testing and so on. If any of you are BMWCCA members, I highly recommend contacting techtalk and asking for a copy of the "old school" plan.

I didn't see anything in that link that supports having to change the oil more frequently than recommended. Just because the oil is clean on two engines (one at recommended intervals, and one at double the recommended frequency) doesn't mean that you need to do it twice as often as recommended.

On the other hand, here is a thread with pictures of an engine that followed the recommendations to 100,000 miles. And it isn't an M model running 10-60, so it is far more relevant.

http://www.xoutpost.com/other-bmws/4...intervals.html

Urban myth. BMW began including prepaid maintenance in the US because potential purchasers were afraid of the dealer prices for maintenance. It was a US program designed to level the playing field. If a high percentage of dealers hadn't been ripping off BMW owners they wouldn't have needed to do it.

It is more telling to note that BMW holds the residuals on all of their leased vehicles, and is happy to do so for extended lease periods, despite the apparent risk of their oil change intervals.

Also interesting that you don't even need to follow the BMW oil change recommendations for BMW to take your used vehicle into the CPO program and put an extended warranty on it, at their risk. BMW don't worry if you go over 20,000 miles on oil changes before giving you a CPO warranty, without even looking at the engine.

FSETH: I guess if you really wanted to be old school you would find a supplier for the API SH oil that was current when many of these vehicles were produced. Bias ply tires are old school too.

Just poking at you, I think owners should do what feels right for them. It is just that there is all this talk of a conspiracy to make our engines fail sooner. I would like to see evidence of engine damage by following the manufacturer's recommendations, thats all.

I think there is some truth to what Noodle said. The BMWCCA plan also touches on this. I find it hard to believe it is just a coincidence that when BMW started paying for "scheduled" maintenance these intervals started increaseing exponentially. Granted some technology advances like longer life oils came about, but some items like brake fluid and coolant change intervals were doubled although the fluids themselves remained unchanged. Seems very questionable, IMO.

:thud:...Maybe we need a Stickie that links to the literally
pages and pages of Full Threads, on this site, that cover this oil
change interval debate. :rolleyes:

To the OP: if you want to change oil/filter more frequently than rec'd,
have at it, and feel good. :thumbup:

To the lessee that wants to double up those oil changes, the next owner
will be appreciative, maybe. ;)
GL, mD