Cummins on oil webpage

[jnelson]

doing some research on oil I found this cummins webpage. Seems they recommend the same drain intervals for synthetics as dino oils. some pretty good info ---http://www.cummins. dk/fileadmin/dokumenter/Pdf_filer/Cummins_Litteratur/Olie_3810340-04.htm

 

[Gary - K7GLD]

YUP - sez so right here:

Synthetic Oils



Use of “synthetic engine oils” (those made with API group 3 or group 4 base stocks) is permitted subject to the same performance and viscosity limitations of petroleum (mineral) based engine oils. The same oil change intervals must be applied to synthetic oils that are applied to petroleum (mineral) based engine oils.

 

[AKaiser]

What are the odds? I found the same document today looking at whether I could run Amsoil 5w30 HDD. I have a thread too. What are the odds?

 

[BTowler]

I would like to know the reasoning behind this. A good quality synthetic is far superior to dino oil in all respects, it does not coke up, viscosity actually improves with higher temperature, higher film shear, etc. etc. which all adds up to longer lifespan. Just saying you shouldn't won't keep me from extended drain intervals, if they show a good reason, then thats another story.

 

[RustyJC]

Perhaps Cummins is operating on the theory that they want the oil changed to get rid of contaminants (e. g. , soot, weak combustion acids, condensation, fuel dilution, etc. ) rather than because the oil itself is degraded.



Rusty

 

[BTowler]

That is why you change your filter at 3-5K and the oil at 15-20K.

 

[RustyJC]

Changing the filter doesn't get rid of all the contaminants I listed. Again, I'm just speculating on Cummins' thought process - that there's more to oil change intervals than the condition of the lube oil base stock and/or additive package. I guess if you really want to know Cummins' rationale, ask them.



Rusty

 

[AKaiser]

I would like to know the reasoning behind this. A good quality synthetic is far superior to dino oil in all respects, it does not coke up, viscosity actually improves with higher temperature, higher film shear, etc. etc. which all adds up to longer lifespan. Just saying you shouldn't won't keep me from extended drain intervals, if they show a good reason, then thats another story.

Does viscosity improve at higher temps, or does it just suffer less degradation than conventional oils at the same temp?



As for why they recommend against extended drain, I suspect it's just CYA. Truck companies and the military have been doing oil analysis and extending drain intervals sucessfully for years.

 

[BTowler]

Both, that is why only synthetic oil is used in turbine enginges. Dino oil will start to seperate and coke at higher temps leaving unprotected surfaces, synthetic will continue to hold a film at temperatures far exceeding dino oil.

 

[RustyJC]

Not all turbines utilize synthetic oils - see HERE. Aircraft jet engines and aeroderivative industrial gas turbines utilize synthetics because of their unique design and the high temperatures encountered by the lube oil, but "heavy" industrial gas turbines are another story.



Rusty

 

[AKaiser]

Not all turbines utilize synthetic oils - see HERE. Aircraft jet engines and aeroderivative industrial gas turbines utilize synthetics because of their unique design and the high temperatures encountered by the lube oil, but "heavy" industrial gas turbines are another story.



Rusty

I'm guessing that BTowler was refering to aircraft turbines.

 

[BTowler]

Not all turbines utilize synthetic oils - see HERE. Aircraft jet engines and aeroderivative industrial gas turbines utilize synthetics because of their unique design and the high temperatures encountered by the lube oil, but "heavy" industrial gas turbines are another story.



Rusty

My reference was to aircraft engines, should've clarified that, sorry.

 

[RustyJC]

Even so, aircraft turbine oils utilize an ester (Group V) base stock (typically polyol ester), not the more common polyalphaolefin (Group IV) or "pseudosynthetic" ultrarefined petroleum (Group III) base stocks used in most automotive synthetics. Aircraft turbine oils are an entirely separate beast!!



Rusty

 

[Gary - K7GLD]

I would like to know the reasoning behind this. A good quality synthetic is far superior to dino oil in all respects, it does not coke up, viscosity actually improves with higher temperature, higher film shear, etc. etc. which all adds up to longer lifespan. Just saying you shouldn't won't keep me from extended drain intervals, if they show a good reason, then thats another story.

Contamination of engine lube oil by soot and a wide variety of other combustion by-products degrades synthetic lubes just as much as dino oils, and those need to be eliminated regardless of which oil type is in use.



Someone will jump in here and state that use of a bypass filter takes care of many of those by-products and allows extended drain intervals with synthetics (I've been in these discussions before! ), which is true - but then, you can also do the same thing with dino oils, synthetics aren't the only oils that can use extended drains with appropriate oil bypass filters.

 

[BTowler]

Even so, aircraft turbine oils utilize an ester (Group V) base stock (typically polyol ester), not the more common polyalphaolefin (Group IV) or "pseudosynthetic" ultrarefined petroleum (Group III) base stocks used in most automotive synthetics. Aircraft turbine oils are an entirely separate beast!!



Rusty

What Makes It Synthetic?



Synthetic oils are considerably more expensive than petroleum motor oil, and that’s because of how they are made. The name “synthetic oil” means that it is chemically synthesized from different hydrocarbons. The manufacturing process starts with a hydrocarbon, derives the gas ethylene, and then chemically synthesizes that into the base stock for synthetic oil, polyalphaolefin (PAO). PAO’s are extremely slippery man-made polymer chemicals with molecular strength and lubrication characteristics unsurpassed by any other lubricating fluid.





FULL SYNTHETIC VS. SYNTHETIC BLENDS



Many synthetic motor oils today are blends made with an ester base and contain petroleum oils as a carrier. These oils typically contain 70 to 85 percent synthetic esters by volume, with the balance being additives that are dispersed in the petroleum carrier oil. Semi-synthetics contain only about 10 to 15 percent synthetic esters as a base stock.



The problem with ester-based oils is that they still contain petroleum and suffer from the same problems that pure petroleum oil does: They start to break down at high temperatures and relatively low mileage (about 5,000 miles at the outside).



True synthetic oil, on the other hand, contains no naturally occurring substances and doesn’t need to be thinned out with additives and detergents before it can be used in a vehicle. In fact, the oil actually works as a natural detergent to clean out old engine deposits that may be remnants from petroleum oil used previously in the motor.



True synthetics don’t break down at high temperatures and cause oxidation, nor do they cause sludge and block passages. Synthetics have a very low (below -40° F) pour point which make them ideal for use in extreme low-temperature conditions.

 

[RustyJC]

That reads like something from an Amsoil "technical" paper. AFAIK, Redline is the only widely available ester-based (Group V) automotive synthetic. The others are Group IVs (PAOs) or Group IIIs.



Let's look at something a little more objective - HERE:

Synthetic oil as a motor oil



The majority of oil lubricants, including many motor oils, are mineral oil distillates of crude oil. However, synthetic motor oils also have a share in the market. Historically, synthetic motor oils have been made from the following classes of lubricants.



Polyalpha-olefin (PAO) = American Petroleum Institute (API) Group IV base oil



Synthetic esters, etc = API Group V base oils (non-PAO synthetics, including diesters, polyolesters, alklylated napthlenes, alkyklated benzenes, etc. )



In the last decade of the 20th century, hydrocracked and/or isomerized (Group III) base oils began to be used in motor oils. These oils are also designated as "synthetic" in the United States.





Automotive Use History



Although in use in the aerospace industry for some years prior, synthetic oil first became commercially available in an API-approved formula for automobile engines when the French Oil company MOTUL introduced a commercial ester-based synthetic-oil in 1971. Other early synthetic motor oils included All-Proof, a 10W-50 polyolester-based motor oil introduced in 1970, Amsoil, introduced in 1972 (with a diester-based 10W-40 formula developed by Hatco) and Mobil 1, introduced in 1974 (with a PAO-based 5W-20 formula).





Required Applications



Many modern high-performance vehicles specify synthetic motor oils. Some manufacturer specifications include:



GM-LL-B-025 (diesel engines)

GM-LL-A-025 (petrol or gasoline powered engines)

VW 502. 00/505. 00/503. 01 (includes both diesel and petrol or gasoline engines)

MB 229. 5 (DaimlerChrysler)

BMW Longlife 01

Honda HTO-06

Porsche Approval list 2002

Some Briggs & Stratton small engines.



Various motor oils made from Group III, Group IV, and/or Group V base oils are on the market that meet one or more of these manufacturer specifications.

Rusty

 

[RustyJC]

The problem with ester-based oils is that they still contain petroleum and suffer from the same problems that pure petroleum oil does: They start to break down at high temperatures and relatively low mileage (about 5,000 miles at the outside).

See page 3 of the following brochure. On page 3, the brochure points out that Mobil Jet Oil II (which owns about 70% of the aircraft jet engine market) utilizes a polyol ester base stock.



Rusty

 

[AKaiser]

Contamination of engine lube oil by soot and a wide variety of other combustion by-products degrades synthetic lubes just as much as dino oils, and those need to be eliminated regardless of which oil type is in use.



Someone will jump in here and state that use of a bypass filter takes care of many of those by-products and allows extended drain intervals with synthetics (I've been in these discussions before! ), which is true - but then, you can also do the same thing with dino oils, synthetics aren't the only oils that can use extended drains with appropriate oil bypass filters.

That's no lie, and I've read where the difference between modern dino oil and synthetics has been narrowed, in general. There's also the TBN issue, which will be a bigger issue with 2007 emissions, due to TBN additives causing emissions equipment failure. Glad I got my 2005.

 

[BTowler]

I don't want to start an oil war, so to cut it short, the documentation you provided supports my original statement, whether it is ester based or PAO. The excerpt I provided refers to motor oils specifically and is not propoganda material from any of the synthetic manufacturers, it is an excerpt from a magazine article on synthetics. Also, your link lists Amsoil as an ester base, unless they have changed thier formula along the way.

 

[RustyJC]

I don't want to start an oil war, so to cut it short, the documentation you provided supports my original statement, whether it is ester based or PAO. The excerpt I provided refers to motor oils specifically and is not propoganda material from any of the synthetic manufacturers, it is an excerpt from a magazine article on synthetics. Also, your link lists Amsoil as an ester base, unless they have changed thier formula along the way.

No, it says the original Amsoil formulation was ester-based. Their current advertising touts Amsoil as being PAO-based - see HERE for an example.

100% Synthetic PAO Formulated Basestock Technology Makes AMSOIL Best in Synthetics

Rusty