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      07-19-2011, 12:38 PM   #21
First Lieutenant

Drives: 2008 328i
Join Date: Sep 2010
Location: Tucson, AZ

iTrader: (0)

Entity, sorry; I misinterpreted the tone of your post.
I have changed the oil on this car three times; far more than is recommended by BMW. Overkill? Probably, but I bought it off of a lease and the oil still came out pretty dirty this last time around. ... but that's a bit off topic so I'll post more details on this below the main stuff.

First time I changed the oil: added 7 quarts. When done, the dipstick read exactly full. That's on both the stalk reading and on my Navi reading.
Second time I changed the oil: added 6.5 quarts. When done, the dipstick read exactly full. Again, on both stalk and Navi.
Third time I changed oil: added 6.0 quarts. When done, the dipstick read exactly full on both stalk and Navi for two days. Yesterday afternoon, the stalk reading started showing it halfway between full and minimum. The Navi showed it down 2 bars from full (there are 5 bars between full and minimum). It reads halfway down today.

My concern is that the e-dipstick seems to be very insensitive to overfilling. I talked to my indy BMW mechanic and he said that his manual shows that my car takes 6 liters of oil. That comes to 6.34012 quarts.
So when I put in 7 quarts and 6.5 quarts, I was overfilling my car with oil.

Now, as whether or not I've overfilled a car when changing the oil while following the listed capacity. Yes. A car that states 5.0 quarts with oil and filter change generally comes up just a little above full after adding 5.0 quarts. I chalk that up to the fact that you can't completely drain the oil and that the oil containers probably contain just a bit more than specified. As CEB mentioned above, oil capacity and oil fill after an oil change are two different things. This is a reason why many of us purposely underfill by a little bit.
My oil currently reads between min and max. Is that within specs? Yes. Would it be better if it were exactly full? I doubt it. Would it be worse if the car is overfilled with oil? Yes, excessive overfill can result in foaming the oil due to the crankshaft. Not a good thing. And now since it appears that the e-dipstick is insensitive to overfilling, I have real concerns.

As far as electronic ignition, timing, etc, most of those were positive advances in auto reliability. Can anyone tell me how replacing a manual dipstick with an e-dipstick is an advancement, especially since oil is the lifeblood of an engine? OK, I don't get my hands dirty when I 'check' my oil level. But popping the hood on occasion and taking a look at everything is, IMHO, a good thing. It gives you a chance to see if anything else looks out of place.

/oil change interval rant on
OK, now to changing my oil more often than recommended. I don't like BMW's recommended oil change intervals due to possible sludge buildup in the engine. I also don't use LL-01 oil; I use Castrol Edge 5W-30. It's a great oil and I switched from Mobil 1 a couple of years ago after finding out that after Exxon bought Mobil, they were using inferior formulation on Mobil 1 in order to increase profit margins. I'm happy with Castrol, as BMW must also be, as my oil fill cap has a Castrol logo on it.
This last oil change was after only 4,000 miles but was 7 months after my previous change. I live in the desert southwest and it can be a pretty harsh environment - it ain't the rolling hills of Bavaria.
I'm sure many will view changing the oil often as a waste of money. That's fine. It costs me ~$47 for each oil change ($32 oil, $4 for auto hobby shop lift, $11 for oil filter). All things considered, that's a pretty reasonable price to pay for not worrying about the lifeblood of my car.
LL-01: The spec is for longlife oil. I don't believe that you can make an oil that works 'good as new' for two full years and can prevent sludge buildup. I'd rather simply change my oil more often. I'm sure some will adamantly disagree with my practice of changing oil twice a year. That's fine. The worst that can be said is that I'm wasting my money. I can live with it costing me $95 a year in oil changes - I waste a lot more money than that on other stuff.
When my oil comes out some other color than pitch black, I'll cut back on changing it. My wife's Acura doesn't get its oil changed as often (has 75K miles; went 6K miles between changes) and the oil is less black than for my car. ... I know this because I changed them within a couple of weeks of each other.
To those who advocate BMW specs for oil changes, what is it that makes a BMW so 'special' that it can go so many miles and so much time between changes? LL-01? Take a look at other companies that offer free maintenance (Volvo, VW) - 7500 miles on Volvo, 10000 miles on VW. You'd think if LL-01 was that great, Volvo and VW would require LL-01 and change their oil change requirements to match BMW.
Cynical question: What happens to an engine that doesn't have its oil changed often enough?
/rant off