Oil change


I have a 2002 BMW325xi that I bought with 42000 miles on it. I had the oil changed soon after, because I did not have record of that from the seller. The dealer has told me to change the oil every 15K miles or once a year, whichever comes first. The mechanic locally who has done some minor stuff says every 5000 miles and I’ve read every 7500 miles in other places. What is the best interval for oil changes? I’m confused. My husband says go with the dealer. I just want to drive the car and not worry about this stuff.

thanks for any help.


No way would I ever allow a vehicle to go 15k without an oil change.

7500 is acceptable if you do a lot of open road driving.
If you do a lot of short hop/stop and go then I would say 5000 maximum, but my personal preference is around 3500-4000 tops.


could the confusion be …whether synthetic vs regular oil?


Simply do it twice a year, every spring and fall. That might work out to an oil change every 4000-6000 miles for most people. You don’t have to worry about keeping records.


you are all wrong, change the oil when it starts to change from brown to black, and when it gets thinner.


Forget all except what your owner’s manual says about changing oil. That is the final word, your owner’s manual. Who would know better than the people who designed your car and endurance tested its engine. Dealers and mechanics don’t do those things.


“you are all wrong, change the oil when it starts to change from brown to black, and when it gets thinner.”

You can’t be serious.


well i am, its not the miles, its how you drive them, blackening oil, and or thinner oil (not when its hot) are a sign of wearing out, i dont mean to wait until its completely black, just when its more black than brown.


Yes. And BMW has specific oils that pass specific tests in order for them to go 15,000 miles. Your owners manual will explain that as well. You probably need the BMW LL01 designation which is (to my knowledge) always synthetic.


PS- I would change it at 7500 anyway.


I hope you’re kidding. If you want to change oil based on the condition of the oil, spend $20 and have an oil analysis performed. You can’t tell anything by looking at the color.

BTW, I would probably use about half of the manufacturer’s recommendation (about 7500 miles) with a good synthetic that meets the bmw specs. Oil is cheap, engines are expensive. If you really want to know, have an oil analysis done.


You probably need the BMW LL01 designation which is (to my knowledge) always synthetic.

According to the Mobil 1 website, that’s correct:



I completely agree. Color of oil has little to do with condition. They aren’t even the same color right out of the bottle. Some additives darken quicker than others. If you want to beat your brain senseless with motor oil info, go to bobistheoilguy.com.



BMW uses a Long Life spec’ed oil that your local Jiffy Lube or other shop won’t have in stock.

This special oil coupled to an 8-9 quart oil(typical is 4-5 qts) capacity allows your engine to run much further on its motor oil.

If your going to do once per year just make sure it meets proper spec. Mobil 1 is quite popular just make sure they install the proper grade/spec at your garage or dealer.


Cathy: What type of driving do you do? Do you take mostly long trips? Are you a soccer mom who has a dozen or so short trips every day? Is the weather always hot? Always cold? Do you drive down a dusty road or driveway on your way home? Many factors should be condsidered here, but the easy answer is… if you aren’t mechanically inclined and don’t really know, protect your expensive BMW by finding a good mechanic and have your service done when he/she tells you to. Rocketman


Say, are you related to Star882, or whatever his name was?


That funny that Mobil carries an oil for BMW. Friend of mine owns a 2004 BMW and in the manual it says NOT to use Mobil-1. ONLY oil APPROVED is Castrol Syntec. He really doesn’t care since oil changes are free anyways.


Must’ve changed supplies- my sisters (I think an 02) says Mobil 1. However, most oil bottles have a list of what specs they pass. If you pay for the test, might as well publish it.



i hope you dont think it is too much to ask to pull out your dipstick and check the quality of the oil every 4000 or so miles


I drive a diesel and it is black after one mile. You can’t tell a thing by color, even in a gasoline car.


The guys who designed that engine did their homework and figured out what kind of oil and how often to change it. The then printed that information in the owner’s manual. That is where you will find the answer to your question.

Don’t rely on the dealer to give you the right answer on this one.