[mc68386]

Originally Posted by Silver 325i

Do any of you providing opinions on oil change intervals have any basis on why you think oil needs to be changed every 3k or whatever? I am a mechanical engineer and design automotive parts, (not engine parts) but I know that all auto parts are tested for the expected life of the product and are no failures are permitted. I am confident that BMW has 1000 of hours of engineering and testing into the engine. Just because the manual of a honda or a toyota or a 20 year old BMW says to change the old every 3k does mean your car needs to be. Advances in oil and material science can likely account for engines lasting longer with less oil changes. I would love to buy a car and never change the oil and see how long it last. I bet it will go pretty long, but the oil manufactures don't want you to know that.

Who cares what this oil analysis says, who is to say X ppm of X material causes the engine to break before 150k or whatever.

For one thing, until BMW offered free oil changes, they required an oil change at 1250 miles. Not on a 20 year old Honda but on a BMW from 5 years ago. Why do you suppose they did this? Has there in the last 5 years been some advancement in engine technology that makes metal flakes no longer harmful? I doubt it. I don't like sand in my underwear, and I doubt my 330 likes metal flakes in its oil.

For another thing, engine builders who build engines for racing change oil right after break-in (after <100 miles in some cases.) They aren't interested in getting 300,000 miles out of the engine, but the absolute best performance.

I grant you that it's obnoxious and obsessive, but it's also cheap insurance. And if we weren't obsessed, how many of us would be here?

[tiga901]

Originally Posted by Black325i

How come my manual says the first oil change is 22,000 km ? Why are folks changing at 5,000 miles ?

We are in the US....we use miles here!!!!

[silverado]

Originally Posted by mc68386

For one thing, until BMW offered free oil changes, they required an oil change at 1250 miles. Not on a 20 year old Honda but on a BMW from 5 years ago. Why do you suppose they did this? Has there in the last 5 years been some advancement in engine technology that makes metal flakes no longer harmful? I doubt it.

For all we know BMW might have started running these engines for a while and discarding the oil as part of its post production/pre installation testing of an engine.

As I said before, to think that BMW would decide to throw away their hard-earned reputation for building long-lasting cars and engines to save on oil changes in the US is ludicrous. Remember that BMW does not offer free maintenance all over the world, yet they still have the same recommended oil changing intervals.

[england1987]

thanks for the info, that eases the nerves

[F32Fleet]

Originally Posted by Silver 325i

Do any of you providing opinions on oil change intervals have any basis on why you think oil needs to be changed every 3k or whatever? I am a mechanical engineer and design automotive parts, (not engine parts) but I know that all auto parts are tested for the expected life of the product and are no failures are permitted. I am confident that BMW has 1000 of hours of engineering and testing into the engine. Just because the manual of a honda or a toyota or a 20 year old BMW says to change the old every 3k does mean your car needs to be. Advances in oil and material science can likely account for engines lasting longer with less oil changes. I would love to buy a car and never change the oil and see how long it last. I bet it will go pretty long, but the oil manufactures don't want you to know that.

Who cares what this oil analysis says, who is to say X ppm of X material causes the engine to break before 150k or whatever.

I'd say 90% off everyone who changes the oil on their BMW's every 5-7k miles does so because #1 They like to work on their cars, #2 Makes them feel better, #3 Don't believe BMW since BMW only moved to 15k mile intervals and "lifetime fluids" when they started offering free scheduled maintenance.

BMW knows most people, regardless of their current intentions, will not keep the car beyond 100k miles.

[poldim]

I dont plan on keeping the car for over 100k, so I wont be wasting any more money. I'm hoping that the damage done during the first 15 wont be lethal to the engine. As I am sure BMW has tested this.

[radionomad]

Maybe changing just the filter would be sufficient insurance against particle contamination!