Diesel oil in gas engine
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Many have said that it is more robust oil.
I believe that if it carries the gaoline spec of SL or SM then I dont see a problem using it.
I believe that if it carries the gaoline spec of SL or SM then I dont see a problem using it.
Typically no, there should be no issue. However....one concern for you in particular, living in New York, would be temps. If you're using a 15W40 in winter, that's going to be a bit more start-up wear because the 15W cold viscosity is going to be a tad thicker.
JHZR2
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Please do a search. I know some say it is lousy, but it really does work OK if you know how to use it.
It has been covered umpteen times...
JMH
It has been covered umpteen times...
JMH
I use synthetic Rotella 5w40 in VW gasoline engines. It works well, and saves money.
As long as the diesel oil also meets API SL or SM, you will be fine putting it in gasoline engines.
As long as the diesel oil also meets API SL or SM, you will be fine putting it in gasoline engines.
1. Diesel oil has better/more add packs. - good for engine wear.
2. The oil is a bit thicker than gas engines normally are spec'd for.
2. The oil is a bit thicker than gas engines normally are spec'd for.
Though I tend to agree with all that's said above, a part of me ponders how diesel oils may far against many a short trip uses, where as fleet use is likely to have the engine used hours at a time. It appears this "feeling" might be solely in my head, as UOA's don't seem to show anything for those whom have posted.
That said however, I've used RTS and Delo alone and in addition to my regular PCMO for over the past 2 yrs. I've since used such in my yard equipment as well. Less expensive for the confidence level it makes me feel, and gets the job done.
There's much to be said for doing what feels right, yes?
Take care.
That said however, I've used RTS and Delo alone and in addition to my regular PCMO for over the past 2 yrs. I've since used such in my yard equipment as well. Less expensive for the confidence level it makes me feel, and gets the job done.
There's much to be said for doing what feels right, yes?
Take care.
I have been using Esso XD3 in my Saab 9-3 SE for 2 years with great UOA's. I recently had an emmisinos test down, and the guy thought m y car was brand new since the numbers were so low (car is 2001). I realise you guys cannot get XD3 down there, but Rotella I have been told is very similiar to XD3 or is it Delvac(help),
Iam currently running Elf 5w40, then try some GC when its colder, the Motul next spring. If my UOA's are not better or on par with the XD3, I will be returing to the XD3.
PS I am running 15.5 PSI (stock) and these engines are known to be hard on oil.
Iam currently running Elf 5w40, then try some GC when its colder, the Motul next spring. If my UOA's are not better or on par with the XD3, I will be returing to the XD3.
PS I am running 15.5 PSI (stock) and these engines are known to be hard on oil.
Emissions test DONE*
If the fleet (diesel) oil is SL rated and the correct viscosity for your temperature range you are good to go!Thats all I use and my UOA's say my engines are happy with it!
I have a 1993 F-150-I6 with 184,000 miles. I use Rotella 15w40, have been for about 100,000 miles. No problems, of course I live in South Carolina where it may get down to 0 degrees about 2 days a winter.
I too can't figure out the search feature. I usually find a whole bunch of stuff that I'm not looking for.
I too can't figure out the search feature. I usually find a whole bunch of stuff that I'm not looking for.
There are some diesel engine rated oils on the market which may still have some ZDDP in them. However, there are problems associated with using these oils in a normal gasoline engine which can become severe in a high-performance gasoline engine.
One issue is the high amount of detergent additive, and another is the high viscosity.
High detergent oil has a lower surface tension and lower shear pressure rating which can cause higher bearing wear in gas engines. A diesel engine needs oil with very high detergent capabilities in order to hold the large amount of combustion byproducts in suspension, but it is not optimized for a gasoline engine. The bearing journal size-to-displacement ratio on a gasoline engine is designed around the use of a lower detergent oil and relies on a high-shear rating to the oil.
The other problem with high detergent oil is that it actually reduces the friction reduction that the ZDDP affords, especially in a high-performance, high valve spring pressure engine.
The viscosity rating of most diesel rated oils is higher than optimum for our higher revving gasoline engines, and can cause oil starvation in bearings at high rpms.
BTW, racing oils have similar problems when used for other applications.
One issue is the high amount of detergent additive, and another is the high viscosity.
High detergent oil has a lower surface tension and lower shear pressure rating which can cause higher bearing wear in gas engines. A diesel engine needs oil with very high detergent capabilities in order to hold the large amount of combustion byproducts in suspension, but it is not optimized for a gasoline engine. The bearing journal size-to-displacement ratio on a gasoline engine is designed around the use of a lower detergent oil and relies on a high-shear rating to the oil.
The other problem with high detergent oil is that it actually reduces the friction reduction that the ZDDP affords, especially in a high-performance, high valve spring pressure engine.
The viscosity rating of most diesel rated oils is higher than optimum for our higher revving gasoline engines, and can cause oil starvation in bearings at high rpms.
BTW, racing oils have similar problems when used for other applications.
"Some" ZDDP left in them?? All engine oils, well almost all and any you can find in your local store still have "some" ZDDP in them, and diesel oils have a bit more than "some".
And then this makes no sense and seems to contradict itself in the same paragraph, "High detergent oil has a lower surface tension and lower shear pressure rating which can cause higher bearing wear in gas engines. A diesel engine needs oil with very high detergent capabilities in order to hold the large amount of combustion byproducts in suspension, but it is not optimized for a gasoline engine. The bearing journal size-to-displacement ratio on a gasoline engine is designed around the use of a lower detergent oil and relies on a high-shear rating to the oil."
Diesel oil has a lower shear pressure rating??? What is this shear pressure rating? Cannot be HTHS as most common diesel oils have HTHS > 4.0 while many gas engine oils are < 3.0. Yes soot handling is higher w/ a D-oil, but due to the Law of Diminishing Returns I don't think a D-oil has a significantly lower surface tension than a strict S-rated oil, or at least those diesel oils that are commonly used and rated for fleet applications with TBN's in the 10-12 range. Maybe this is referring to those D-oils with > 25 TBN ratings which AFAIK are not used outside of heavy industrial applications. Yes most mixed fleet/diesel oils use a very small amount of additive such as silicon to lower the surface tension of the oil to minimize foaming, but this is not a bad thing for gas engines.
And then this, "a gasoline engine is designed around the use of a lower detergent oil and relies on a high-shear rating to the oil."
Maybe this refers to a higher-shear rate instead of rating, as in one that shears more easily, and the only thing that a higher shear rate is used for is fuel economy, there is nothing in the mechanical "design" that I know of that is dictated by the shear rate of the oil. Rather the opposite is true AFAIK, the minimum shear stability of the fluid is dictated by the design.
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