2010 Cadillac CTS, 3.0L, 38k; 7.1k on Mobil 1 5W30

[Colt45ws]

OLM was at 29%.
My Grandpa's highway ride. He had it changed by the dealer in July. In August he took it to Michigan, then went on to Las Vegas before returning here to Washington. So, it goes without saying that the majority are highway miles.
I was certain they had probably put in the new Dexos ACDelco oil, but after looking around Im 99% sure it is Mobil 1 5W30 SN.
Code:


Iron 17

Aluminium 3

Copper 5

Silicon 5

Sodium 96

Potassium 5

Molybdenum 81

Boron 44

Magnesium 643

Calcium 1149

Phosphorous 655

Zinc 786

Fuel 4.0% - GC

Visc 8.8cSt@100C

TBN 3.37

Oxid 13

Nitr 22

Fuel Dilute is higher than I expected. I drove this for about 20 miles before I parked it on the ramps. The sodium is also a little bit odd. Im not sure where that wouldve come from. Ill have to watch for it next time.

It has Pennzoil Platinum 5W30 in it now. I think, given the fuel Ill have him take it to 50% and see what happens.

 

[oilboy123]

He doesn't warm it up before driving off does he? Just a thought on the high fuel.
I believe sodium is from antifreeze.

 

[Colt45ws]

I dont know, maybe. I did catch him once idling it just because. I told him that was not good for it; but I dont know if I got through.
Oh yeah, Lab is Polaris. In case anybody wondered.

 

[The Critic]

Sodium is likely an additive. Maybe they did use the ACDelco oil?

 

[Colt45ws]

I doubt it. The additive levels do not match the VOA on here in any way. The biggest tell is probably Mg/Ca levels. This shows 643/1149 and the VOA shows 0/2260. If you look at the M1 VOA I linked, it matches the additive levels almost perfectly.

 

[Pablo]

Na could be from previous oil (or native in oil), dirt or filth or soap ingress, or a coolant leak.

 

[Patman]

Calcium seems very low in this report, I thought M1 had way more than that amount in it?

 

[JAG]

Originally Posted By: Patman
Calcium seems very low in this report, I thought M1 had way more than that amount in it?
That's how the M1 5W-30 API SN version is. Magnesium was increased to somewhat compensate for the lower calcium.

 

[ltslimjim]

Originally Posted By: JAG
Originally Posted By: Patman
Calcium seems very low in this report, I thought M1 had way more than that amount in it?
That's how the M1 5W-30 API SN version is. Magnesium was increased to somewhat compensate for the lower calcium.


Probably my take as well...not sure about the sodium, though? Previous oil was ______?

 

[Colt45ws]

Dont know previous oil.. This is only the second change since he bought it. Couldve been anything.

 

[ltslimjim]

Originally Posted By: Colt45ws
Dont know previous oil.. This is only the second change since he bought it. Couldve been anything.


Oh, well there you go. Well, I don't like the iron numbers especially with Si down, but it isn't terrible or anything. Not sure what the universal averages are, if any were given? That would help for this engine.

Fuel dilution is definitely a big concern, at least an area of interest at this point. Has this car seen any PEA containing fuel system cleaners?

 

[Colt45ws]

Yeah, Im not too concerned with the Na at this point; too early to tell what it may be from.
Universal Averages are not given by Polaris. This engine seems to have a higher iron number on average. I found one from a 3.6L (Which is essentially the same engine) with 16 iron in 7.7k on PP. It was also a higher mileage engine AND it was a older port injected model; so little fuel dilute.

 

[ltslimjim]

Okay, so the Fe is alright. I wonder what would be causing the fuel dilution? The oil thinned out some, but did okay otherwise with the presence of fuel.

 

[JAG]

Fuel was measured by GC which is more accurate and generally will measure higher than how Blackstone does it which is calculate it based on flashpoint. So we are just used to seeing underestimated fuel percentage measurements because most UOAs we see use the less accurate method of measuring it.

 

[ltslimjim]

Ah, very interesting. I totally didn't know they had a distinctly different method, but I'd imagine you are correct in that it's more accurate.

 

[Colt45ws]

Yeah, and the flashpoint they pick is all over the map. I can't figure out how they determine what the minimum flash is supposed to be. Ive seen them use all the way from 355 to 385F. And the way they do it, is every 20F below that number is 1% fuel.
For example, on my last report from them on my CV, it showed flash was 385F and <0.5% fuel. Well, the minimum flash they have on it is 355F. So, of course it is zero. In reality it was probably about 1%.

 

[Gene K]

Originally Posted By: Patman
Calcium seems very low in this report, I thought M1 had way more than that amount in it?


Thats normal since they added the Magnesium.