This is one of those subjects that gets far more discussion than it probably deserves. Most everyone agrees that 15,000-mile oil change intervals are not in the best interests of the car if real longevity is a concern (150,000 miles and up). Beyond that, the debates begin. So in the interest of reducing worry by owners of new or still-young Bimmers, I thought everyone might like to see what the inside of a high-mileage, well-maintained engine looks like. These are photos of the valvetrain of an M54B25 engine in a 2001 325xi. The oil and filter have been changed approximately every 7500 miles since the car was new. The only oils ever used are Mobil1 5W30 and BMW High Performance Synthetic 5W30. Filters are OE BMW parts. The car is driven ~50 miles per day, mostly highway commuting miles, for pretty much every week of its life except when I was on non-driving vacations. This engine is just over 210,000 miles old. It pulls strongly, smoothly and easily to redline and in terms of power and torque feels pretty much the same as just after break-in. It sees 5000+ RPM shifts every day and redline--just shy of the rev limiter--pretty much weekly. It has never been abused but never been babied, either. Oil loss is about 1 quart per 3000 miles. The catalytic converters are original and the car has never failed an emissions check. Please excuse the large dimensions but these are quick, poorly-lit cell-phone shots that will not resize well. This is the VANOS unit and cylinders 1-3. There is some light buildup in the corners of the VANOS housing where oil cannot easily drain away, but nowhere else. This is cylinders 3-6. Note the complete absence of sludge or buildup of any kind. The light gold varnish on non-moving parts is soft enough to be rubbed off with a shop rag. (I tried, in a small spot not in the photo. Calling it "varnish" is almost an exaggeration.) If you look closely at the forward exhaust cam lobe on cylinder #3 (bottom right of this picture) you will see a small variation in the finish--a shinier stripe at the forward edge--which is pretty much the only sign of wear on the cam. The variation is undetectable to the touch, even with a fingernail. I don't regret being unable to provide pictures of the bottom end of the engine. However, I replaced the oil level sensor a few thousand miles ago and found pretty much the same conditions inside the pan. (The tiny bit of it I could see/reach anyway.) These photos are unretouched and the only cleanup I did was to wipe down the gasket sealing surfaces. Other than that, what you see is what I've got. Modern synthetic oils are truly very, very good at keeping an engine clean and resistant to wear. This is perhaps THE classic "your mileage may vary" issue but I hope these photos and description of the engine's history help you decide how to care for yours.
Looks good ! Engine looks good - nice and clean for the mileage. A few comments on oils. Using the correct oil spec for the engine/application is important as different engines have different formulation requirements. Obviously to maintain your warranty you need to use both the proper oil viscosity and oil specification. Modern oils in the last few years and synthetic oils in particular are very good engine oils. OCIs are primarily based on "normal service" which can be somewhat a gray definition. Most OMs tell you that if you operate your vehicle under "sever service" which includes but is not limited to towing, high ambient temps, dusty conditions, below zero temps, short duration drives where the oil never gets to full operating temps, etc. then the oil should be changed more frequently. Driving your car 50 miles per day is actually a good thing as the oil should be getting up to full temp to allow condensation to evaporate. This can reduce sludge build-up and corrosion. Short runs are hard on an engine as are cold start-ups. I'd say keep doing what you're doing and enjoy!
Thanks, NotTheStig, for a great 'photo essay'! As Forcedinduction mentioned, that operating temperature is very critical in combatting sludge and condensation. The correct oil and filter, regular maintenance...what's not to like?! Don
Looks similar to my old 340k-mile M20. Stay on top of oil changes at regular intervals and you'll be fine.
Nice. I don't want this comment to restart a debate, but I feel it's worth noting I've replaced more than a handful of valve covers on cars that have gone by the 15k interval and looked just as clean at 150-160k. A lot of wear is more the product of operating environment as opposed to oil change frequency. As far as "practice what you preach," I'll admit I change my oil every 5k with BMW Hiperf 5w30.
Everyone take a good long look at that gorgeously clean engine bay, then take a gander at these pics! These pics I found online and supposedly was the same sort of engine, only a little newer, M54. Apparently it went 60k without an oil change!
I'm going to puke! regarding the OP, highway driving is nice and good for an engine and longer OCI's. My commute is short, 5 miles each way and I consider this extreme/severe service. I change much more often. I also take occasional extended drives to heat it up properly.
The good news is no car maker suggests 60,000 mile OCIs. I'm certain BMW and other car makers would not be recommending long - up to 15K mile OCIs if they thought this was a problem as they are paying for your engine warranty for 50K miles and they actually conduct testing to determine the appropriate OCIs. As noted by several people above, using the proper oil and changing it at an appropriate OCI makes for a happy, long lasting engine. For those who really want to know when they should change their oil based on the ability of the oil to maintain it's specified viscosity and additive package, you can do Used Oil Analysis, UOA. Then you don't need to guess if you should change at 7,500, 10,000 or 5,000 miles based on your actual driving pattern. Reputable UOA labs like Blackstone or Titan labs do UOA testing for ~ $25. and provide a report on the serviceability of the oil, the contaminants present and wear metals. You can also pay a few dollars extra for a TBN test. The end result will tell you if your OCI can be extended beyond whatever OCI you are currently using. The base oil doesn't actually wear out, it's the additive package that is consumed over time and the oil gets dirty. A UOA will tell you what is an acceptable OCI for your specific vehicle, the oil being used and your driving conditions. BTW, I have no association with Blackstone or Titan but I do use both labs for UOA.
Aim for that engine, I think it would actually help that poor thing. I wished I had photos for an A/B comparison when I wrote the post...I never dreamed anyone would find such a horrific negative example! Thanks for that, az3579 (in a "thanks for scaring ten years off my life, Mr. Kreuger" sort of way). You, sir, are a wise man. (Unless you are female, in which case please substitute the correct pronoun and noun and accept my apology.) I'd also consider that severe duty since the oil barely has time to warm up. I meant to add in the OP that highway driving has as much to do with the condition of my engine as the maintenance. But 25 years ago I've seen engines with similar service lives and a third the mileage that were half as clean. Both engines and oil additives have come a long way. ForcedInduction made some great points, especially the importance of using oil that meets the viscosity and API service requirements, which I forgot to mention. The note about automakers' warranties is also spot-on. I may do an oil analysis some day for the sake of education so thanks for that info. The bottom line for people new to the game is this: If your driving habits are average and you change your oil more often than the recommended bare minimum, you're more conscientious than most people by far. Your engine will probably (barring unrelated failures) outlive your patience with the rest of the car wearing out.
True but the LL-01 specification was developed after this engine and thus was not a requirement. It is unwise to use an oil that does not meet specifications needed to maintain warranty coverage, but these specifications change over time. It is very rare for new standards to be applied retroactively to older engines.
Another Reason to Change the Oil As I painfully (in the pocketbook) recently discovered, the tire manufacturers are now requiring that you rotate your tires every @5k (and keep a verifiable record of it) or they won't honor their warranty. Check YOUR warranty! Continental just pulled this one on me for two rears which wore out after less than 15k (alignment was checked TWICE). So, change your oil and rotate your tires every 5k (sounds like what I had to do with my '72 2002 back in the day!)... Schade und Traurigkeit am Fahren...
A lot of cars have staggered setups, with rotational tires; they can't possibly expect you to rotate your tires with that setup as each wheel HAS to be in its specific corner of the car.
Unfortunately that's nothing new, tire company adjusters have long seized any excuse to deny warranty coverage for wear. There are just too many variables. If they weren't hard-nosed about it, half of us would be rolling on free tires. I know I'm not supposed to laugh, but ....
Rotating Tires Exactly. Moreover, if you only need to bring in your car every 15k for service, how many folks are going to bring the car in every 5k to have the tires rotated. My SA told me that basically, unless they see uneven wear, they don't bother to rotate tires anymore and BMW doesn't really recommend it either. He was as shocked as I was when Continental came back and said that they wouldn't honor the warranty, even though the tires were less than a year old. So we checked the warranties on Michelin, etc., and they all now have the same rotation clause. I'm no tire expert, but I don't recall that being in any warranty I've seen in the past...and neither did my SA or the tire guy at the dealership. If you've got a staggered setup, better check your warranty... Freude am Fahren (nochmals)...
From the 2010 328i Owner's Manual... Page 213 BMW advises against swapping wheels between the front and rear axles, even if all tires have the same size, as this could impair driving characteristics. If the tires are of mixed sizes, swapping wheels between axles is not permissable.
BMW vs Tire Manufacturer From the Continental Warranty (you can find this at Tire Rack's website for every tire): Tread Wearout Coverage The Continental brand tires listed below are warranted against wearout up to the mileage/ kilometers coverage show in this section, even though the actual mileage/ kilometers you may get from your tires may vary because of driving habits and road conditions. Subject to the provisions of Section 5 and 7 below, if one of the tires listed in this section wears out before the listed mileage/ kilometers, CTNA will adjust the tire on a pro-rata basis. "Wearout" means that the tire's tread has worn evenly down to the tread wear indicators (2/32nds of an inch or 1/6 mm of tread remaining.) "Pro-rata" for this Tread Wearout Coverage is measured by the odometer readings at the time of the tire's purchase, as shown by the original tire sales invoice, and at the time of replacement. In addition, you must present a completed rotation schedule contained in the original owner's copy of the tire's Limited Warranty and Adjustment Policy. • Tire(s) that have not been rotated at least every 6,000 to 8,000 miles (10-13,000 Kilometers) as evidenced by a completed rotation schedule are excluded. The other tire manufacturers' new warranties all say the same thing. So BMW says one thing and the tire company says another and the user gets caught in the middle...just great... Kein' Freude am Fahren...
The other tire manufacturers' new warranties all say the same thing. So BMW says one thing and the tire company says another and the user gets caught in the middle...just great... Maybe the thought is...If one can afford a BMW, the costs of tire replacement shouldn't matter. Fortunately for me, I seem to get fairly good mileage from my tires. And my wife got 50,000 miles out of the original set of run-flats (Goodyears) on her 2005 Mini convertible. I think that might be a record or something...
