Quote:
Originally Posted by Crusader
Every now and then someone posts here asking how often should the oil be changed. Is this oil or that oil suitable for my BMW. Then someone else chimes in that the oil should be changed per the service indicator or twice as often or ... Then another emphasizes the oil must be BMW approved or meet such-and-such a specification or your warranty is void. (OBTW, BMW doesn't test and/or approve oil unless the manufacturer submits it to them.)
BMW makes pretty good engines. Back in the seventies when they started making their reputation, 250,000 mile without any internal work (valves, rings, bearings, etc) was common ... with good old DINO oil! Do you think BMW sweats warranty replacements for lubrication prior to 50K or 4 years? You could NEVER change the oil, just add a quart as needed, and the engine would survive the warranty period. Modern engines and lubricants are that good. Of course, the guy that buys the car from you might not appreciate the impact your lack of maintenance has on the engine's remaining service life now that it's HIS engine in HIS car.
The service interval for the N54/N52 tends to be 15-19000 miles. In the past, BMW owners have found their engines have a lot of sludge accumulation with change intervals of that duration. No failures, just sludge; maybe not good in the long run. Given my experience with several Bimmers and other cars using synthetic oil, if you change at reasonable intervals ... 5,000 to 7,500 miles ... and use a good quality synthetic oil (Mobile 1 and its immediate competitors is good enough), in something approaching the right viscosity range, lubrication will not be a problem. My E39 530i, nicely broken in at 95,000 miles, burned less than 1/2 a quart between 6,000 mile changes.
Mobil 1 is not BMW approved (unless it's the 0W40 formula), or is it? In a personal correspondence, BMWNA said it is. Neither is Royal Purple nor Redline, yet both are regarded as superior lubricants in both documented and undocumented reviews. Mike Miller, tech guru for BMWCCA's Roundel and Bimmer, likes Redline at 10,000 mile intervals in his E46 ... and he's got the oil analysis to back up his conviction.
If your car lives at redline, if you live in a harsh environment and make lots of short trips, or if you just want to have the car for 10+ years and 250,000 miles; you might lean toward a more conservative oil change program. If you plan to unload the car before the warranty period, stick with BMW's condition based service interval.
|
I know this is beating a dead horse, but how can you say "BMW owners have found their engines have a lot of sludge accumulation with change intervals of that duration"? I've never read anywhere on the net, in magazines, or from anywhere else that BMW owners who follow the recommended OCIs find sludge in their engines. I've run three (3) BMWs to 256,000 (1989 E30), 152,000 - current mileage (1997 Z3), and my '06 E90 currently at 170,000 miles, all at the respective CBS directed oil change intervals, and none of those engines had or have any sludge in them. That is over 570,000 of combined miles of driving. My E90 at 170,000 miles burns a quart of oil about every 14,000 miles or so with an average OCI of 17,500 miles; but that doesn't prove anything.
If owners want to follow the CBS or change early it's their prerogative; but what is tiring is people who come on this forum and make emphatic statements like yours, which have no basis in truth and are just opinion.
Rant over...