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2015 ATS Sedan / 2.0T / RWD / 6-AT
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Discussion Starter · #1 ·
Hey folks,

a question to the petrol... uhm oil-heads of you :cool:

I have advised an company to do an eninge oil analysis for my 2.0T ATS, I use LiquiMoly Special Tec DX 1 5W30 (Dexos 1 Gen 2) and they have measured that the viscosity of the oil is lower than the minimum limit value. The oil was driven for about 3.100 miles in 8 months.

A 5W30 is supposed to be within 9.3 - 12.5 mm²/s at 100 °C (or 212 °F).

My 5W30 engine oil just hits 7.69 mm²/s at 100 °C (or 212 °F) - and 36.81 mm²/s at 40 °C (or 104 °F).

The viscosity index is at 185.

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They have stated it's caused by a slightly increased fuel entry to the engine oil due to cold starting / short distance driving / technical error. In my case it should be short distance driving (I hope so) and the oil doesn't reach optimal temperature from time to time.

So others recommend to go for a 0W40 or 5W40 (thicker base oil) instead of 5W30 to avoid less viscosity caused by fuel entry.

But with the same requirements:
API SP or API SN+
ACEA C3

But these 0W40 / 5W40 won't match the Dexos 1 Gen 2 approval.

What are your thoughts? 🇺🇲
 

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96 FWB
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[Big Fat Edit]
I had initially posted a simple way to remove the 'fuel in the crankcase from short commutes' from potential problems could be to simply let the engine idle a while after start-up and add that warm-up time before heading to help vaporize fuel out of the oil.
I can offer that I never do that myself as it's just a waste of gas, and it's always just wait a bit to build oil pressure and GO. But Sub-'s post and another below has me officially reversing my advice for doing that for any reason at all.

And over here we're just called wrench-heads or motorheads.
 

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2013 ATS 3.6L Luxury
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I have advised an company to do an eninge oil analysis for my 2.0T ATS, I use LiquiMoly Special Tec DX 1 5W30
Back when I had LS1 Camaros, I researched oils on BITOG, an oil fanatics site. Considered Mobil 1 5w30, but I saw virgin oil analysis posted on BITOG that showed it was right on the edge of being a 20 weight. Used oil analysis of this oil on BITOG showed some where it wandered into 20 weight range.

Since my area gets very hot in the summer, I instead went with M1 Truck & SUV 40 weight, which was almost a 30 weight. But once German Castrol 30 weight became available in my area I went to that. Very popular oil on BITOG, cult like following.

After Katrina damaged petroleum industry facilities along the gulf coast, there were a lot of used M1 5w30 oil analysis posted on BITOG showing significant viscosity breakdown. Speculation was that storm damage had impaired Mobil's ability to make true synthetic M1 5w30, so they were using dino oil based stock and pumping it up with viscosity index improvers. Problem with VIIs is that they breakdown due to mechanical shearing.

If true that Mobil was doing this, it would be very ironic as they had filed a lawsuit as to what could be advertised as a synthetic oil. They lost, opening the door for dino based oil to be freely advertised as synthetic.

So, is that oil a true synthetic that is on the edge of being a 20 weight when new and wanders over with use, with fuel contamination as a contributing factor? Or is it a dino based oil heavily loaded with VIIs that breakdown?

There is a European section on BITOG, might want to research there or join and ask about that oil. Maybe there is a Euro version of BITOG where Euro oil geeks hang out?

 

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2002 F55 STS, 2014 Explorer XLT, F-150
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BITOG is fun for rumor, hearsay, a bit of fact, flaming, witchcraft, old wives' tales, and wars. :cool:

Quite a few CF members use Blackstone Labs for oil analysis. THAT tells you what your engine oil is doing.


Yes - cold running, extended idle periods, start/stop driving is a contributing factor to oil dilution by raw gasoline. Starting an engine and letting it idle to "warm up" is actually one of the worst things you can do to an engine. Either start the car, let it fast idle for 20 -30 seconds, and then drive normally for a few miles before yeeehaaaa!!!! or don't start it at all - let it sit (on a Battery Minder).

FWIW, the GM "DEXOS" label is a minimum functional specification, not a type or brand, for engine oils. Probably every name brand of engine oil on earth meets the specs - what you want is the recommended viscosity ranges for climate and service. Some VVT engines are very demanding when it comes to relatively short oil/filter change intervals.
 

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2014 ATS 3.6 Premium RWD, 2016 Corvette Z06, 2018 GMC Sierra Denali 2500HD Diesel
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My thought is that trying to mask the harm done by excessive short trip and not enough load/time to let the oil stay in the desired temperature range is a really bad idea. Fuel dilution of oil is undesirable even if you start with a heavier range oil, all you are doing is treating one of the symptoms instead of the cause.

If your driving absolutely won't allow avoiding this situations, a block heater will be of immense help to speed warm up time. You may have to also use significantly reduced change intervals. The OLM takes this type of operation into account but perhaps it doesn't penalize it as much as it should.

And as sub notes, idling a cold engine to warm up is one of the worst things you can do because you are compounding the issues of fuel dilution and other contamination. I generally remote start my gas powered cars as I am approaching them so by the time I am inside and belted in, the engine has dropped to base idle and it is ready for operation at moderate speed/load which is how you want to properly warm an engine.

My diesel pickup is a little different because it starts at base idle. With it I give it a few seconds and then back out of the garage and put it under moderate load. And during really cold weather, it has a very nice automatic cold start strategy where the engine slowly ramps up from curb idle to 1,500 RPM while the turbo exhaust vanes are commanded mostly closed and the Allison automatic is engaged with its output shaft locked in order to properly load the engine during warmup to avoid "wet stacking".

I am fortunate to live in a situation for perfect operation of vehicles because I am at a rural address where I don't have to immediately have the vehicle up to high speed and the shortest trip I would ever make would be to the nearby village which is a 10 mile round trip and those sorts of short trips are extremely rare for me. My Corvette Z06 and Camaro RS both have oil temperature gauges and those don't get maximum throttle operation until the oil is up to 180F which takes quite a few miles with the Z06 with its dry sump system even though it uses a engine coolant type oil cooler which serves as an oil heater during initial operation.

Years ago a good friend had a deep sea fishing boat with a pair of Cat turbo-diesel engines. Caterpillar called for starting the engines then engaging the drive within seconds and let them run under moderate load until the temperature gauge began to move off the cold end and at that point the throttle should be greatly advanced to finish proper warmup. That wasn't always possible but it provided a simple idea of how Cat wanted these very large and expensive engines operated.

Rodger
 

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2002 F55 STS, 2014 Explorer XLT, F-150
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Your observation on the Cat engines is in direct agreement with the start-warmup instructions for the pair of Cat 3208-TA diesels in a 48' yacht I used to skipper. Start 'em up, gently load 'em for a while, GO !!!
 

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BITOG is fun for rumor, hearsay, a bit of fact, flaming, witchcraft, old wives' tales, and wars. :cool:

Quite a few CF members use Blackstone Labs for oil analysis. THAT tells you what your engine oil is doing.

Yeah the geeks on there can get kooky.

But the thing I really like about the site is all the VOAs and UOAs that get posted there, solid info to help decide on which oil to use. Blackstone was the most popular lab used from what people posted on there.

If, e.g., the OP can find specific info on that oil showing that it starts off on the low end of 30 weight, then he can consider one that is solidly in the 30 weight range so he has some safety margin after use.

p.s., I won't posted anything like this on other sites anymore after M1 fans on a Camaro board came after me with torches and pitchforks when I dared to advise a newbie to check out the poor post Katrina UOAs being posted on BITOG after they had recommended M1 5w30. :eek: :censored:
 

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one of the reasons I've read for the further updating of Dexos 1 (Gen 1, Gen 2 and now Gen 3) is Low Speed Pre Ignition (LSPI)...one of two motor oils recommended by GM is Mobil 1 (quite possibly because they currently have a marketing agreement with them) but also because of the low Calcium content in their oil...

Last I checked for the LTG 2.0 Turbo (albeit for the 2013 Malibu the GF has) is the regular Mobil 1 5W-30 but could possibly look at the Mobil 1 Extended Performance 5W-30 which is also listed as a Dexos 1 Gen 3 motor oil...

Mobil's own website no longer shows Mobil 1 regular 5W-30 as their recommended oil but that site is wonky and it doesn't even show the LTG optional engine for 2013 (which the GF has) or other information I've tried to look up...YMMV as that same site still shows Mobil 1 regular 5W-30 IS a Dexos 1 Gen 3 oil as their also recommended Mobil Super Synthetic and Mobil Synthetic 5W-30 oils...

Food for thought...

Bill
 

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I change my oil every 3000 miles, and I never do short trips. I do not believe in the "oil analysis" places. I have fixed dozens of cam phasers with ATF in the last 5 years. Nobody can tell me those phaser problems would be there regardless of these ridiculous oil change intervals. Oil is cheap, recyclable, and reusable. Also, I only use ACdelco filters and ACdelco oil. They are both so cheap, theres no reason not to. Using anything but a factory oil filter is asking for trouble. Every single manufacturer has a TSB for some vehicle with such and such code that will set from aftermarket oil filters. I have fixed one Jeep MIL just by installing a mopar filter as advised by TSB.
 

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ZeGerman,

I am in no way an oil expert (I am an electrical engineer by training) but before we get too far into arm-chair oil analysis here, we don't have enough data yet to help so here are some questions to think about:
1. How many miles were on the oil you had analyzed? (Longer the oil is used, the thinner it will get over time)
2. Did you pull the oil sample with a fully warmed up engine? (Blackstone labs in the US says this affects the analysis due to rich running during warm up)
3. What brand/type of oil was in the engine when you drained it for the analysis? (Different brands will have varying viscosities)
4. Did the oil analysis report indicate any unexpected amount of metals or foreign particles?
5. How many oil analyses have you had done? Is this the only one? (Need more than one to see trends)
6. Do you actually drive short distances, i. e. you frequently shut the car off before it is fully warmed up?

The above questions are based on what I've picked up reading Blackstone Labs oil reports, including one of my own ATS in 2017, and also an excellent paper by a Bolivian oil refiner who researched oils for his 1960 Corvair: Classic Car oil (widman.biz). If your oil report doesn't indicate any excessive metal concentrations, then your engine probably is doing just fine. You need more reports on further oil changes to see if you have a trend of fuel dilution. Also, certain brands of 5W30 oil can be "on the edge" of 5W30 viscosities.

For comparison, the analysis done on my ATS's oil (see attached report) on it indicated my viscosity was low too, though not quite as low as yours. Blackstone said it was in the 5W20 range and told me it was of no concern. I had used ACDelco 5W30 Synthetic at this point and I only change my oil when the Oil Life Monitor says to (usually around 5000 miles for me).

Also, definitely do not stray away from Dexos-branded oil. From what I've read, Dexos is specified for many reasons including camshaft phasers for variable valve timing. Using oil that isn't Dexos spec may result in foaming and other nasties that will make your 2.0T rather unhappy. 😃
 

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14BlueRocket...could you share when your Blackstone analysis was done?...you were using the dealership fill of AC Delco 5W-30 full synthetic oil?...your Calcium levels appeared a touch higher than I've seen on other analysis of Dexos 1 oils but that could just mean this analysis was before the Gen 2 or Gen 3 version of Dexos 1 was performed or...

thanks for sharing

Bill
 

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Discussion Starter · #12 ·
@14BlueRocket
to 1) It's mentioned in the text, so the oil was drive for about 3.100 miles in 8 months.
to 2) I cannot remember, but I don't think so. Did it once and almost burnt my fingers in the hot oil during while descrewing the oil plug. So I have taken the sample from the draining oil.
to 3) I use LiquiMoly Special Tec DX 1 5W30 (Dexos 1 Gen 2) since 2019, so I have made three oil changes with this oil before the analysis was done.

to 4) No, the analysis don't indicate any unexpected amount of metals or foreign particles.

to 5) It was the first one. But I've already ordered a second one to do it again next week. So I going to have reference values: 3.700 miles and 9 months of use.

to 6) Yeah, my distance from home to work is about 4 - 5 miles. Possible to solve by bicyle, but due to (night-) shift work ... uhm no :ROFLMAO:

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Thanks for the additional information. I did miss seeing the mileage you list, so thanks for the point.

Was the oil analysis able to actually confirm fuel present in the oil, or was that just a suggestion from the oil analyzer? Forgive me if I'm missing that from your report, but I don't read German and I can't copy/paste their comments above into Google Translate. :D

If this second analysis comes back with similar results, I'd say try a different brand of dexos 1 5W30 and try once more. Liqumoly's datasheet for your oil lists a good viscosity range for 5W30, but trying another oil will confirm if it's the oil or your car. Since your report didn't indicate any significant metal wear, you are most likely not hurting anything by continuing to drive it.

My 3.6 V6 warms up very quickly if I remote start it, let it idle for a minute to two while I get my coat on and head out to it. By the time i drive off from the factory I work at (~0.5 mile to the gate), the engine has reached operating temp. Does yours ever reach operating temp in the 4-5 miles of driving? If not, you could have a stuck open thermostat. I had a Buick that did that and it never developed heat until I replaced the 'stat.
 

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Discussion Starter · #14 ·
@14BlueRocket

Google translate say this:

"Diagnosis of the current laboratory values
The wear values are within the normal range. The fuel content has risen sharply. Cause is unburned
Fuel in the engine oil, due to a cold start, short trips or incorrect fuel entry. Due to the fuel entry is the
Viscosity has dropped and the lubricity of the oil has decreased. According to them, the oil has already been changed.
Clarify the cause of the high fuel entry and eliminate the error to avoid a further increase. Please
after a short time, send a control analysis to the laboratory.
"

The new analysis set will be delivered this week so all in all I think I will have the new results till friday next week. I will keep you updated.
 

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Discussion Starter · #15 ·
As announced, here is the 2nd analysis:

"Iron has increased slightly. The fuel content is increased. However, compared to the previous sample, the value has decreased. Through the fuel entry the viscosity has reduced and the lubricating ability of the oil has decreased. The viscosity is outside the limits of the SAE viscosity class applicable to the specified oil type. If you haven't already, I advise you to do an oil change soon."



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