Mobil1 0w-40, 5006miles, 2007 BMW Z4 3.01si N52

[santov]

Here's the second UOA on my new used BMW. I was excited to do a direct comparo of the OE BMW Castrol to Mobil1 0w-40 for almost the exact same mileage. I use the OE filters which are $10 each, but include a new crush washer and new o-rings for the plastic filter housing.

The first UOA was posted here: http://www.bobistheoilguy.com/forums/ubb...613#Post2137613

For kicks and giggles I'm including my fuel consumption. This is my daily commuter with the occasional sporty driving. It's even easy to work on with the all fluids and filers easy to get at. This is one of the best performing engines I've owned and it returns great fuel economy:

Avg $ per gallon: $3.83
Avg $ per fillup: $39.26

Avg MPG 26.86
Max MPG 30.78
Min MPG 23.32

The first UOA was OE BMW Castrol 5-30, most recent is Mobil1 0w-40.

Could the elevated (ever so slightly) metals be from my driving? (The first UOA was sampled by me, but the mileage was put on by the previous owner.)

Moly was lower compared to the Castrol. I think the sodium and boron are the different recipes.

Tell me what you guys think!

 

[shanneba]

There really isn't any difference in wear.

How long is your commute? Probably > 20 miles a day, mostly highway. That would be long enough to get your 7 quarts of oil up to operating temp.

In California, I would probably stick with the Mobil 1 0w-40 and run it to about 7500 miles.

 

[dparm]

It's negligible, I wouldn't worry unless it keeps going up each time. I agree that M1 0w40 is better.

 

[steve20]

IMO the difference cannot be seen without knowing how the Castrol was driven on. Castrol specs a little better

 

[mva]

Both oils look great.

If it was my car, I would run the BMW 5W30 to take advantage of the slightly better fuel economy that you should get with a thinner oil.

I would also run much longer oil change interval - 8,000 miles would still be conservative with either of these oils.

 

[Artem]

Nice report. I would still with the 5k intervals if it was my car. Of course i would drive it HARD so shorter intervals are a must, IMO.

If the OP is cruising in the car most of the time, 7,500 should be a decent interval, keeping excellent protection as the #1 priority.

 

[SIXSPEED]

Both the Castrol and M1 look like a good match for your car ... the M1 0W40 even stayed in-grade after 5000 miles.

 

[wlyszkow]

I'd stay with 5W-30 - did it better IMO, especially on bearings although I don't like Castrols 5W-30..

 

[Quattro Pete]

Nothing wrong with this report. Looks like 10K mile OCI would be easily doable, although it would have helped to get a TBN.

 

[CATERHAM]

Originally Posted By: mva
Both oils look great.
If it was my car, I would run the BMW 5W30 to take advantage of the slightly better fuel economy that you should get with a thinner oil.
I would also run much longer oil change interval - 8,000 miles would still be conservative with either of these oils.

Actually M1 0W-40 will be lighter than the BMW (Castrol) 5W-30 on start-up due to it's high 185 VI.
If the OP wanted to try something a bit lighter than M1 0W-40 I'd suggest a 50/50 blend of M1 0W/5W-30 and M1 0W-40. The resulting blend will give you an oil with much the same viscosity at operating temp's to the Castrol oil but very much lighter on start-up....just a thought.

 

[SL8R]

Originally Posted By: CATERHAM
Originally Posted By: mva
Both oils look great.
If it was my car, I would run the BMW 5W30 to take advantage of the slightly better fuel economy that you should get with a thinner oil.
I would also run much longer oil change interval - 8,000 miles would still be conservative with either of these oils.

Actually M1 0W-40 will be lighter than the BMW (Castrol) 5W-30 on start-up due to it's high 185 VI.
If the OP wanted to try something a bit lighter than M1 0W-40 I'd suggest a 50/50 blend of M1 0W/5W-30 and M1 0W-40. The resulting blend will give you an oil with much the same viscosity at operating temp's to the Castrol oil but very much lighter on start-up....just a thought.


The OP lives in San Jose, California, where it is almost never below 0 celsius. Isn't M1 0w40 thicker than the BMW (Castrol) 5w30 at anything greater than about -10 celsius?

 

[dparm]

Either get the TBN measured next time, or go to 7500 and see what happens. I'm betting 7500 is the sweet spot.