2008 Mercedes C300, Mobil 1 0w-40, OLM OCI (~11k)

[d00df00d]

The purpose of this UOA was to see if there was any obvious problem with running the spec oil for the spec OCI in this car. Looks like it's more or less okay. It's hard to say anything definitive without a better suite of tests, but for various reasons we are not going to be nitpicking very much about oil in this application.

This is my Mom's car. She bought it used with a little over 10k miles on it. It saw a few highway trips but was mostly driven in moderate traffic on suburban roads. I wouldn't be surprised if it was idled a lot, too. That probably explains the fuel dilution and flash point. No top-off was ever needed as far as I know, so I'm guessing consumption was negligible.

Apparently the previous owner of the car treated it very mildly. That, combined with the low total mileage on the car, probably mean the engine was still breaking in. Keep that in mind when you view the report.

 

[Johnny]

I think it looks very good for the second change. My sister runs this oil in her 2008 C300 and her wear numbers went way down after the third or fourth oil change. She drives almost 90% city, stop and go driving and she has hers changed every 10K.

 

[cchase]

Oil has thickened some, unless it has changed from the PDS.

Was the oil changed with the engine cold?

 

[d00df00d]

Originally Posted By: cchase
Oil has thickened some, unless it has changed from the PDS.

Was the oil changed with the engine cold?

The oil was drained hot.

The sample did sit for a few months before we sent it out, though. I'm told that shouldn't affect it, but...

 

[BobFout]

Originally Posted By: cchase
Oil has thickened some, unless it has changed from the PDS.

Was the oil changed with the engine cold?


The latest PDS shows the newer, thinner, M1 0w40. Previously it was 14 cSt @ 100C.

 

[d00df00d]

Thanks, Bob. I thought that was the case but I couldn't find the exact number.

 

[BobFout]

Originally Posted By: d00df00d
Thanks, Bob. I thought that was the case but I couldn't find the exact number.


It was in my head

 

[Ayrton]

This does NOT look like Mobil 1 0w40, does it?

Did the dealer do this, you personally?

This looks like the NON-ESP Formula M 5w40. Perfectly approved oil.

The Calcium is much lower in Formula M like this. HOWEVER, the magnesium in this doesn't match Formula M either.

I'm thinking this is something else. Some dealers use an approved Valvoline 5w40 product. That may be this.

Has the oil now been changed, or was this just a check?

I didn't do this test on my car at similar mileage, so I do not know how bad the early wear was. What I can tell you, I'm pretty confident you'll see the wear go down dramatically in the next change/analysis.

I do think there is some other kind of oil in there though, not M1 0w40.

 

[Ayrton]

Just to add...

08 was last year of 13,000 mile intervals.

It is now 10,000 miles. This number makes me feel a bit better.

 

[Ayrton]

Just to note, factory fill is loaded with magnesium. It's a shell product with 900 ppm magnesium.

The magnesium may be left over from that.

Still, I strongly believe it's not 0w40 M1 due to Calcium and Boron numbers.


Non-ESP Formula M *OR* the Valvoline 5w40 product some dealers use. Both perfectly approved.


Again, no issues with your report, I was just trying to figure out the oil for you.

 

[BrianEM]

This was a full oil change done by us.

As far as we know, that car was originally purchased and serviced at the same dealership where we purchased it and have it serviced (for all warranty work...we're doing oil/oil filter/air filter changes). The dealership says they use M1 0w40, so we're assuming that's what was in there.

 

[Ayrton]

Originally Posted By: BrianEM
This was a full oil change done by us.

As far as we know, that car was originally purchased and serviced at the same dealership where we purchased it and have it serviced (for all warranty work...we're doing oil/oil filter/air filter changes). The dealership says they use M1 0w40, so we're assuming that's what was in there.


Cool Brian,

Well, I think you'll see something a bit different on the next analysis. You'll see your Calcium and Boron much higher.

Not many dealers use the 0w40 anymore it seems, but it was an approved product, and that is what counts.

I do think your Iron will no longer be a worry at the next change. Keep enjoying this car. It's fun to drive.

 

[d00df00d]

Good catch, Ayrton. Thanks for your attention to detail.

To clarify: My brother performed the most recent oil change with Mobil 1 0w-40, but this UOA is on whatever the dealership put in.

I seem to remember a conversation in which someone at the dealership suggested that they "sometimes use 5w-40." I will try to find out for sure what oil they used for this change. You're right that it doesn't really matter a whole lot for the car, but I'd like to get it right for the sake of BITOG posterity.

 

[BrianEM]

Yeah our mom LOVES the car...Justin and I, eeh...it's nice to drive, it's amazing at what it's built for, but in the end it's kinda boring. That's just personal taste and preferences though.

Yeah the 0w40 was a no-brainer for us to pick for the current fill too, partially because it was on sale at pep boys for 5qts and an oil filter for $30, so we just got two sets of that and have a bit left over. They didn't have the right filter for the Mercedes, so I just picked two filters for my car and put a Mercedes filter in hers

yay free filters!

 

[buster]

Which Mobil 1 is this? Mobil 1 0w40 doesn't use Mg.

 

[Quattro Pete]

Originally Posted By: buster
Mobil 1 0w40 doesn't use Mg.

As Ayrton pointed out above, Mg could be leftover from the factory oil. This is only this car's first oil change after the factory oil was drained.

 

[Steve S]

The next UOA, if you are going to do one will tell something . The oil did good. you got your $$$ out of the oil.

 

[BrianEM]

buster, the thread title and numerous posts point out what oil this is. Never hurts to read a thread before commenting on it

Steve, agreed, although it technically wasn't our money...car came with this oil in it

 

[buster]

Yeah thanks Brian, but it's still unknown as to what the oil really is....probably a Shell product.

 

[d00df00d]

Spoke with the dealership earlier. They said they always use Mobil 1 0w-40 but it's possible that that fill was Formula M 5w-40, and they can't check on it because it wouldn't be recorded anywhere. Bummer.