Gas & Diesel oils closer then ever?

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It seems that we are starting to see lighter weight Diesel oils now 10w30's and 5w30's and new diesel regulations on emitions resulting in lower zink and phosphorus oils for diesels it seems to me that gas and diesel oils are getting closer in specifications then ever would this be correct? And do you think in several years there will be little difference between the two oils to a point that they will be the same?
 
Speaking for passenger cars...most of oils here are double rated... API SN/CF (full saps)

5w30 is prefered on market...in 99.9% in low saps version (acea Cx... X= from 1 to 4)
 
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Depends on the engine.

For passenger cars, there is a greater similarity than in trucks.

As the light duty diesels have gotten more powerful, the recommendations for lighter oils have either disappeared completely, or been shifted for cold weather climates.
 
Originally Posted By: DoubleWasp
Depends on the engine.

For passenger cars, there is a greater similarity than in trucks.

As the light duty diesels have gotten more powerful, the recommendations for lighter oils have either disappeared completely, or been shifted for cold weather climates.


We have combo here.....LDD + passenger cars (gasoline and diesel).....either acea A3/B4 for full saps.....or acea Cx for low saps ( those equiped with DPF filters)...

5W30 is now most widely used grade here...previous it was 5w40 or 10w40.....now EU wants to fight emissions more, thats why we are turning more towards sea 30 grade....EVEN towards sae 20 grade......but I personally doubt that sae 20 oils will work out on long run....

Too much turbos....DIs..... downsizing and longer drain intervals here over the pond
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Wise drivers are still using thicker sae 40 oils....
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Originally Posted By: Kamele0N
.now EU wants to fight emissions more, thats why we are turning more towards sea 30 grade....EVEN towards sae 20 grade......but I personally doubt that sae 20 oils will work out on long run....

Too much turbos....DIs..... downsizing and longer drain intervals here over the pond
wink.gif



Regarding sae 20 oils......my personal opinion is that that "oily water"
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will be reserved for hybrids here
 
ATF is indeed in 0w20 or 5w20 range....

LV versions go even lower

Man I will never put that oily water not even near my car
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Right now I'm using a semi-syn 10w30 PCMO that is SN and A3/B4.

I too have wondered how close this is to a semi-syn CJ-4 HDEO. They both share the same 3.5 minimum HTHS. I suspect the TBN would be pretty close too, around the 10 mark, give or take a little.

The HDEO probably has higher Zinc / Phos levels than the SN PCMO. But I could always step it up to the synthetic Edge 5w30 which is also A3/B4 but API SL due to it's elevated Zinc / Phos levels. This is the Oz Castrol Edge that's BMW LL-01 and MB 229.5, and not the north American ILSAC GF-5 Edge which is a different beast altogether.
 
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Originally Posted By: Kamele0N
Speaking for passenger cars...most of oils here are double rated... API SN/CF (full saps)

5w30 is prefered on market...in 99.9% in low saps version (acea Cx... X= from 1 to 4)

Our diesel oils are generally E7, E9, with occasional E6, E7, E9 options, with the latter being observed as 5w30 CJ-4/SN, generally speaking.

The biggest difference I've ever seen between an A3/B4 and an E7, E9 would be SA. When it comes to the E6, there are the phosphorus limitations, too.
 
In Europe, pretty much all oils are gasoline and diesel compliant, since the ACEA specs insist that both are included, either by combining the 'A' and 'B' specs, or by including diesel and gasoline requirements in the 'C' categories. The same goes for the OEM specs - BMW, VW etc have both types covered.

Many OEMs are holding off on really thin oils in diesels, but Volvo specify a 0W-20 in their new VEA diesel engines.
 
If anything, diesels, running cooler, can most likely tolerate thinner oils than even petrol engines. Especially engines operated in the winter, where there's real issues with engines heating fully up.

Sure, thinner oil comes at the cost of slightly elevated wear, but there is little evidence to suggest that this is actually detrimental over the reasonable economic service lives of engines. Modern synthetic oils have very high viscosity indices, meaning that they actually stay in grade over a wider range of temperature conditions. Thermally induced reduction in viscosity is also a thing of the past with VHVI oils.

IMHO, the automakers and their engineers aren't out to blow up your engine prematurely, or sell a premature replacement. They're optimizing based on the data which fairly clearly shows that the thinner oils have not been to the meaningful detriment of engine life.
 
Peak temperatures for a diesel are likely to be higher, although bulk oil may be lower, depending on the service type - a heavy load (eg towing up an incline) will soon see temperatures rise.

The biggest worry from the engineers is the lower HTHS values and protecting the crankshaft from the thumping great torque from the diesel combustion cycle.
 
Originally Posted By: Camprunner
It seems that we are starting to see lighter weight Diesel oils now 10w30's and 5w30's and new diesel regulations on emitions resulting in lower zink and phosphorus oils for diesels it seems to me that gas and diesel oils are getting closer in specifications then ever would this be correct? And do you think in several years there will be little difference between the two oils to a point that they will be the same?


No, they arent really getting closer then ever, they have always been close.
Diesel C rated oils have always been in the same weight range as Gasoline rated S oils until the EPA started mandating higher MPGs in automobiles 2 decades ago which started pushing the gasoline engine oil weights lower. Now with better technology the C rated USA oils seem to be catching up in the lighter weights again as I assume truckers start to accept them as a way to save fuel with little engine wear increase.
Now, yes they are pushing lower zinc levels to benefit pollution control systems on these vehicles.

Many people do not know, so called "Diesel oil" in the USA is also rated as a "Gasoline oil".
Most Diesel rated API CJ4 oils carry the Gasoline API SM symbol as well and its always been that way, carrying the qualifying API gasoline S.
Its just the consumer who thought otherwise, that Diesel oil is for Diesel engines only, when quite clearly the API donut on the back shows otherwise.

Europe is much the same, I actually like their system better, way more complicated but not really.
They have dual purpose oils such as A3/B4 which is good for just about any gasoline or diesel automotive engine. But unlike the USA they also have the true commercial oils that carry no gasoline certifications as "E" oils, typically E7,E8,E9 etc its these E oils that are close to the USA "C" ratings. CJ4, CH4, CI4, etc.

Granted, oil formulations are becoming ever more complicated, thanks to who we elect to serve us in office, like an government agency, we allow them to run business the way they run government and everything gets screwed up *L*
 
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