Ammar545i

Alright, so I picked up Mobil 1 10w 30 full synthetic extended performance for my 545i. Is this too thick for this car?

NoQuarter

BMW says 5w30. No reason to pick a 10w - it is just thicker before the oil is up to operating temp and your engine gets no benefit out of oil that is thicker at start up. I would suggest a 0w30. Go with the thinnest cold oil you can get. It will be the same viscosity at operating temp (the 30 rating ) .

Ammar545i

damnn, I already changed it with the oil....I should be good though right? haha that is why I asked this.

AchtungE60

No, you need to change it immediately with a different weight or when you reach 4000 RPM cold your engine will blow.

jaycal3

Below is right from the Mobil 1 site... and why would you care enough to ask but not care enough to wait for the answer???

Here:
Current Vehicle:Year:2004Make:BMWModel:545iEngine Type:8cyl. 4.4Liter Naturally Aspirated
Mobil 1 0W-40
Mobil 1 0W-40 is an advanced full synthetic motor oil that helps extend engine life by reducing engine wear and oil breakdown. Mobil 1 0W-40 provides outstanding performance under all operating conditions and meets or exceeds the warranty requirements of many leading car builders


And this is from the BMW site itself:
http://www.bmwusa.com/standard/conte...ngineoils.aspx

inktoxicated

i used the mobil the bmw and recently fuchs from germany. dont feel any diffirence. there all priced around the same

BimmerFan52

I tend to lean towards an approved LL-01 oils, but far more important that exactly which brand oil or which weight you use it that you change it often.
5K miles between changes for normal driving with full synthetic oil. More often if you do stop and go driving or lots of short trips.

Older engines tend to introduce more contaminants (gasoline, soot, coolant, unburned gases, condensed water vapor) into the oil, necessitating more frequent changes. Changing the oil more often greatly reduces the chance of sludge forming.

I strongly recommend full synthetic oil for any engine, and lean towards oils that have the first number as 0W (example 0W-40). This denotes good low ambient temperature starting as there are additives in the oil that help the oil flow at low temperatures. The first 5 seconds during start up are the highest wear on the engine and a free flowing oil will give protection (getting oil between friction surfaces) the fastest.

Oil additives make a base oil, which is basically a straight weight oil, act as a lower weight oil during start up, and act as a higher weight oil during operation (hence the multi-viscosity rating of 0W-40. However, oil additives, including detergent which keeps dirt suspended in the oil so it doesn't settle on and adhere to engine surfaces, don't last long. Once the additives are used up the characteristics of the oil changes and bad things start to happen. Samples of oil removed during testing suggest that after 7K to 8K miles of normal use many of the additives are gone. And remember that oil life is really measured in hours, not miles. Severe testing done by the oil industry to qualify oils for certain ratings is always measured in hours, but the recommendation for oil changes is always expressed in miles operated.

Low average speeds (think stop and go driving) means many more hours of operation than high average speeds (highway driving with few stops) for a given set of miles driven.

If I were driving my BMW every day in stop and go traffic and averaging 12-15 mph for the trip, I would have absolutely no hesitation in changing my oil every 3K miles with full synthetic.

Sound excessive? It is all up to you. It is your engine and it is very expensive.

phlfly

0W-30 Castrol with SPT. But I'm going next time with Mobil 0W-30, I don't see a reason go with long life oils as I'm changing each 5-6 thousand miles anyway. i'm still reading about oil.

jasperxli

+1

BimmerFan52

More than anything, long life oils load up on additives.

Walmart sells M1 Extended Performance oil (read more additives) 5W-30 in a 5qt jug, which here in Scottsdale is $27 per jug or $5.40 per quart.
M1 0W-30W in a 5qt jug sells for $24.97 or less than $5 per quart.

The M1 0W-40W I use in my 545i (also a long life oil) sells for $6.47 per quart. I like the good flow on start up (low temp pour point) and really like the additives for high heat operation here in Scottsdale during the summer. These characteristic are obtained through additives.

Not a big difference in price, and not a big difference IMHO between major name brands of full synthetic.

But again, closely examine how you drive and at what speed on average. Your oil only knows hours of operation, not how many miles you travel.

I used to drive 45 miles to work in 45 minutes, or about a mile per minute. 5000 miles took 83 hours.
For another person who commutes 12 miles across the city in an hour 5000 miles takes 416 hours.

The longest and most severe engine oil test: "Sequence VG engine test" runs for 216 hours, and if motor oil passes this test it is suitable to be licensed under the latest API and ILSAC quality classification (API SM or ILSAC GF-4) - yet that represents MAXIMUM SAFE service interval of only 3,888 miles for someone that averages 18 MPH in typical city traffic !

12mph average? 2,592 miles of safe oil change interval.

If you leave your BMW computer trip computation set for a continuous trip it will compute your average speed for you.

Change your oil based upon estimated hours of operation, not based upon miles driven.