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Discussion Starter · #1 ·
See attachment. Let me say that I am less than pleased. Fuel dilution at 3.1% means there is about 6 ounces of gas in the oil. Report suggests excess idling may be the culprit. It did idle for about 20 or 30 minutes during the delivery process when the "concierge" was explaining features/functions. The fact that the engine is still wearing-in could also factor into it. Or the fact that my wife's typical drive is 10 miles to and 10 miles from work. And it could also be that MB's gasoline direct injection engines are no better than GM's gasoline direct injection engines with respect to this phenomenon. I had hoped for better. Either the fuel dilution or fuel dilution combined with mechanical shearing has caused the oil to drop to a viscosity of a 20 weight (8.6 cSt). Either way, I am extremely uncomfortable leaving this oil in for another 8,000 miles. The whole situation certainly calls for additional and frequent testing until some trend can be established.
 

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Very interesting. Coincidentally, I use the same lab in Indy for analysis of the power steering fluids that I work with, but hadn't thought of sending them my motor oil. I'm already past 10K and had "A" service done at the dealership.

Sample collection method can greatly influence the analysis results. For power steering fluids you get different levels of contaminant and wear metals depending on whether the sample is pulled from top or bottom, and how long the system has been stationary before the sample was taken.

How did you take the oil sample at 2K miles? I'm assuming you didn't drain from pan oil plug. Any chance that if you pulled the oil from the top you are getting a higher concentration of fuel? Thinking gasoline is lighter than engine oil, so maybe concentrated at the top?
 
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Sample was taken immediately after engine was shut off following the wife's 10 mile drive home from work. I use a MixMizer syringe (sold for measuring two-cycle oils for mixing) attached to a rigid plastic tube inserted down the oil dipstick tube until it will not go any further then backed out a smidgen. Tools are always cleaned with soap and water after each use.

I will be posting additional analyses as they occur. As a matter of fact I have another one out right now that was taken after a 250 mile trip to see if by chance the accumulated gas will evaporate off with extended use but my prior experiences with a GM 3.0L HFV6 suggests that it will not.
 

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Sample was taken immediately after engine was shut off following the wife's 10 mile drive home from work. I use a MixMizer syringe (sold for measuring two-cycle oils for mixing) attached to a rigid plastic tube inserted down the oil dipstick tube until it will not go any further then backed out a smidgen. Tools are always cleaned with soap and water after each use.

I will be posting additional analyses as they occur. As a matter of fact I have another one out right now that was taken after a 250 mile trip to see if by chance the accumulated gas will evaporate off with extended use but my prior experiences with a GM 3.0L HFV6 suggests that it will not.
Do you have any more oil analysis reports from this oil or subsequent oil changes? How many miles were on this oil? I'm guess 2,000 because you mentioned not wanting to put 8,000 more miles on this oil.

I changed my oil at around 2,300 miles, but did not send any off to be sampled.

Thanks,
Jeff

EDIT: I just searched and found many more reports from you, but haven't had a chance to look them over. Thanks
 

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Any diluted fuel was not due to idling at delivery. That is long evaporated. Short trips make for fuel dilution.

In any case, I would like to see more comprehensive viscosity numbers. That test report is useless for me. I use Blackstone Labs instead.

Also do not aspirate oil for analysis. When the oil is drained let it drain a bit and take a sample in mid-stream.

FWIW, I did change the factory fill at 2000 miles.
 

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Thanks for the response. I, too am interested in seeing reports from Blackstone regarding this engine. They seem to be the gold standard. I got rid of the factory fill around 2,300 miles, but did not save any for testing. Oh well.
 

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My incoming car has been on-lot down in FL for ~190 days, with who knows what sort of short drives, test drives and the like.

Plan is to have the factory fill changed prior to delivery - or is that a bad idea? Seem to recall that the factory fill may have some special additives to aid in break-in but I could just be imagining that.

Anyway - I'll see if I can get samples for Blackstone as I'm very interested in this topic myself.

Then plan is to change at 2500-3000 miles after break-in, then at 5K intervals. I just don't trust a 10K interval in these cars with the power output, turbo, et cetera . . .
 

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IMHO ...

Give it a good long run to boil (simmer) the water out of the oil.

The break in oil is different (I've been told MB uses recycled oil, but our guide at AMG didn't know anything about that).

I'd keep it in for at least 2500 to 3000 miles, but not much more.

I have my maintenance chart prepared for 5K between oil changes. I agree with your assessment. If the oil looks good, I might extend that. But I'll need to base any extension on the results.

Remember that these motors are fine instruments ... you need to carefully bring them to thermal equilibrium before you start having fun ;-)
 

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Very interested to hear that you folks are changing oil as early as 2K miles initially. I am of opinion that this is indeed a very good practice that will invariably prolong engine longevity. I abhor the idea of first oil change at 10K miles. But I understand that European auto designers want to minimize the carbon foot print not only to the manufacturing process but as well as effectively reducing waste products by extending the life cycle of expendable fluids. BMW LL01 synthetic oils was rated at one point 25K miles or one year, and they eliminated oil dipstick completely, so that "garage queens" like myself don't drain the oil prematurely. Of course this contributed to premature engine problems, and they have since revised to 10K miles or one year.
 

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Changing the factory fill at 2k miles (or so) is a good thing.

Now to the OP: Do you drive your car in the ECO modes? That is a sure thing to run the engine sub-optimally. Now that your break-in is done, take it often to the open road and do an "Italian Tune-up". You know what that is right?
 
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