BMW Synthetic 5w30 - 5,500mi in 2010 BMW 750Li

[ARH_0700]

Report from our 7 series with the new twin-turbo DI V8. Wear looks good considering the engine beat the heck out of the oil. Looking at the flashpoint and viscosity, it looks like typical DI fuel dilution is at play. Oil temps are very well controlled in this engine with two large oil coolers. Typical range is 210-220F, with 245F the max I've seen under spirited driving in 95 degree ambient temp. GC 0w30 went in for this OCI, which will probably be 6500 miles.

 

[Quattro Pete]

Nice little beast you've got there.

Surprised the fuel dilution isn't as high as on some other DI reports.

 

[chubbs1]

Nothing wrong with that UOA! Nice ride! I like the good dose of moly that oil has in it, FP of 360? Anyway I would be confident in the wear in of this engine. Thanks for Posting

 

[Jim 5]

Thanks for posting this. I have been really interested in how these turbocharged DI engines are going to wear.

 

[superunknown]

Really nice ride, and it seems that oil managed a relatively harsh lifetime fairly well. I'm interested to see how the GC will do in relative and absolute terms. Thanks for posting.

 

[ARH_0700]

You're welcome, thanks for the comments

I'm also curious to see how GC and later M1 0w40 compare, so I may take some more samples in the future.

 

[Jim 5]

I'd love to see the sample on the GC.

 

[saaber1]

Fuel dilution does look high to me. Flashpoint is lowered significantly, Manganese is high. Remember Blackstone only extrapolates fuel from the flashpoint, it doesn't measure fuel.

Despite fuel dilution it looks like the oil did well at this 5500 interval. I'd like to see what the UOA would look like with some of the ester-based oils that have shown to deal well with fuel dilution in the Audi/VW 2.0 FSI DI turbo engines.

The hidden concern here is valve deposits. UOAs obviously do not show what is happening to your valves but the flashpoint depression and viscosity loss can be indicators that elements such as broken long-chain viscosity modifiers may be making it to the valves through the PCV. We have quite a few examples of the V12 DI engine being plugged up big time by around 50k miles (not the same engine though). If this were my car I would get a Dyson analysis because you may be able to retard the growth of valve deposits somewhat through your oil choice.

What is the starting viscosity of this oil? What % loss in kv100 is there in this UOA? That would help quite a bit.

 

[JoeFromPA]

I'd prefer the new formulation of Mobil 1 0w40 for this engine and application, personally. I'm not a GC nut, as I think better oils can be found for the same price, or less, and with greater ease of locating them...

Awesome ride and impressively low metals considering the engine is probably still in break-in...then again, you've got a large sump too