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      07-19-2011, 01:34 PM   #22

Drives: 2006 325i Sport
Join Date: Jun 2006
Location: Virginia

iTrader: (0)

Originally Posted by iflyjetzzz View Post
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
So first off, I should have done this originally, thank for your service to our country. Highly respect you guys that are career Military. I was always jealous of the guys I worked with from Ft. Meade who had access to the fort's car repair facility.

If you read my posts on the subject of oil, I'm on the side of longer oil changes. I have over 500,000 miles of experience of adhering to BMW's long oil change intervals on the three different BMWs I've owned (all since new), so it's not conjecture on my part when I state that it is safe to follow the CBS OCI. But we’re not here (nor am I trying to start) to discuss the OCI issue.

Now a recent event with my e-dipstick between my last oil change and the current, active, oil in my engine now was this:

At about 16,000 miles on my last oil, my car was down 1 quart and notified me of that status. Dumbass me kept forgetting to add a quart for the next three days (until the weekend came up). Now for me, 3 days of driving is about 500 miles and the owner’s manual says to add a quart within 200 (IIRC) miles after the notification comes up. Well when I went to check the e-dipstick prior to adding the oil it went back up to 3/4 quart low. So being concerned about over filling, I didn't add the quart. Eventually about 6 weeks later I started having a few slight performance issues, like the engine would skip a beat or two. Soon after, the 1 quart low signal came back up, I immediately added the quart (I kept it in the trunk just in case). The e-dipstick read full. A few weeks later, the e-dipstick started dropping the level fast; 1/4 quart low one day, then a few days afterwards 1/2 quart low. Then, 3/4 quart low. Well by this time I was within 1,500 miles of an oil change, so I changed the oil, and I was thinking my oil level sensor was going bad. I measured the drained oil and sure enough there was 6 and 1/4 quarts that drained out. So even though I added a full quart, my engine was still low on oil and my e-dipstick reported full. But in this case I didn't add the oil within the mileage interval BMW calls for, which may have set the dipstick to read faulty.

During this time I discovered I had a few instances of the VANOS fault codes showing up in the ECU. The point of my story is; I think the engine is designed to run with a minimum of 6 quarts in the sump as to provide enough oil volume to properly control the VANOS system. I eventually pulled the VANOS control solenoids and cleaned them and swapped them between the intake and exhaust cams. After now about 8,500 miles everything has been normal. I also think the e-dipstick (oil level sensor) is of such a design that it does not give an “instant” measure of the oil level (such as a mechanical dipstick does). I think the system is designed to be reset, assumes there was 7 quarts added at refill, and starts its monitoring sequence anew. Adding less than 7 quarts of oil probably messes with the software (I’m just guessing).