Who has concrete, peer veviewed studies on oil change and wear?

[hammersley]

I for one am tired of opinion's on this subject, because they're like (bu_ _ holes) - we all have one. What I want to see is a long term test that actually takes a fleet of trucks, driven similarilly, and run them on different oils and different change intervals. Tell me where that study exists!!! Fleets get a million miles with dino and good change intervals. Even though I don't use a group 4, (I do use PB 2000 extreme) I pay a bit more because when I change the oil, it cleans up very well from my hands and gloves. Not scientific, but better than any other I've used. NOW - if I only had some real good data... ... ... I smell something rotten in Denmark with this oil thing. Could it be that the oil companies don't want us to know that in real world applications, using proper regular maintenance,

that there may not be any difference with the oil we use. That, as they say in politics, may be one of those very inconvient facts!

 

[illflem]

Seems like most of the fleet studies find the best one is the brand that the oil manufacturer gives them for free.



Here's probably the best known unbiased study, is 22 months and 4. 5 million miles in NYC taxis enough?

http://www.xs11.com/stories/croil96.htm



"No brand performed best



The bottom line. In our tests, brand didn't matter much as long as the oil carried the industry's starburst symbol. Beware of oils without the starburst; they may lack the full complement of additives needed to keep modem engines running reliably.



If you've been loyal to one brand, you may be surprised to learn that every oil we tested was good at doing what motor oil is supposed to do. More extensive tests, under other driving conditions, might have revealed minor differences. But thorough statistical analysis of our data showed no brand-not even the expensive synthetics-to be meaningfully better or worse in our tests.



Oil changes: How often?

The bottom line. Modern motor oils needn't be changed as often as oils did years ago. More frequent oil changes won't hurt your car, but you could be spending money unnecessarily and adding to the nation's energy and oil-disposal problems.



Even in the severe driving conditions that a New York City taxi endures, we noted no benefit from changing the oil every 3,000 miles rather than every 6,000. If your driving falls into the "normal" service category, changing the oil every 7,500 miles (or at the automaker's suggested intervals) should certainly provide adequate protection. "

 

[Diesel Gunner]

I am not saying that it can't happen, but oil companies supplying oil for free? Maybe to produce that data that we are discussing, but not for an entire fleet, forever. I mean, they are in the business to make money, not give it away. Now, I will agree that race teams might be supplied with free petroleum products, so large trucking firms may be contracted to test new products at no charge. Seems logical to me.



Sure, if I owned a fleet of trucks, I would love the free oil. If I felt that the free oil was the root cause of many of my rigs losing engines, I am sure that I would not feel so good about the stuff.

And, if the manufacturer of that particular product went on record stating that their product was the be all and end all of all lubes, you can be sure that I would be in court to collect some of that money that they would be making from their falsehoods.



With that said, there are some skank companies out there. However, the more prominant names can be trusted and there are many small companies that are operaating and have always operated above board. It costs alot of money to collect the data that we are talking about and that is added into every gallon that is sold.



Now, I doubt that Chevron is ever going to pay for Shell oil to run a side by side test and publish the results. I mean what would they do if the Shell product proved to be superior? Then also remember that statistics and numbers can be manipulated (what does a four ball test prove anyway?).



At best, all we can do is research the products to the best of our ability in order to make the most informed decision we can. If truck A's engine lasts 5000 miles more that truck B that was using a different oil, was truck B's oil better? Thats to close for me to call.

 

[hammersley]

I remember this test as well.....

It was good as far as it went. I did like this atatement:



"We intended to compare the results of these tests with those from the three taxicabs whose Mobil 1 was changed at our normal interval, every 6,000 miles. Unfortunately, two of the three engines using the 12,000-mile interval developed problems. (We couldn't attribute those problems to the oil. ) The third engine fared no worse than the three whose oil had been changed at 6,000-mile intervals.



The bottom line. Modern motor oils needn't be changed as often as oils did years ago. More frequent oil changes won't hurt your car, but you could be spending money unnecessarily and adding to the nation's energy and oil-disposal problems. "



It was interesting also that the actual mileage for any car wasn't very much. I still think my initial thoughts are correct - and the oil companies wouldn't want to dispell us from finding out that there is essentially nothing different... ... .

 

[Joseph Donnelly]

"Uncovering the Problems with Extended Oil Drains" by Jim McGeehan, _Machinery Lubrication_, Sept-Oct 2001, pp. 24-29. The article considered ring wear, stuck rings, piston deposits, seal life, soot-pollishing wear, filter plugging, head-deck sludge, bearing life, camshaft wear, etc.



"An oil sump is like a toilet: you have to flush it. Considering all the factors, the OEM recommended oil drain interval, combined with high quality engine oil provides the best insurance of engine durability. "

 

[amsoilman]

A few years back (1995) there was a SAE Technical Paper written about this very thing.



Here are some excerts from that paper.



A Synthetic Diesel Engine Oil with Extended

Laboratory Test and Field Service Performance





ABSTRACT



This paper describes the engine test and extended oil drain field performance of new synthetic engine oil technology developed for use in North American low-emission heavy-duty Diesel engines. The resulting formulation utilizes an advanced additive system specifically tailored for synthetic base stocks which exceeds current industry and engine builder targets in critical performance tests. Use of synthetic base stocks allows the formulation of engine oils with a unique combination of performance characteristics, which include meeting SAE 5W-40 viscosity requirements for cold starting benefits while maintaining low volatility loss at high temperature for oil consumption control. In addition to meeting API CG-4, CF-4F, CF-2, CF, ** and EC requirements, this technology has also demonstrated exceptional performance in extended-length Diesel and gasoline engine tests. Furthermore, it has also performed very well in extended service interval field tests.

At drain intervals up to four times those normally recommended, excellent engine wear, deposit protection, and oil consumption control have been consistently demonstrated. Additionally, fuel economy benefits in excess of 4% relative to SAE 15W-40 conventional mineral oils have been documented.



The desire to reduce costs associated with the operation of heavy-duty diesel engines has prompted considerable interest in extending the mileage and/or time between engine and vehicle service intervals. Extended service intervals for engine and other vehicle lubricants offer the potential) for multiple cost benefits. Lower cost for consumable materials (lubricants and filters), reduced labor costs for scheduled

maintenance, less out-of service time for engines and/or vehicles, and lower expenses for disposal of used oil and filters are several potential benefits that could be realized by extending service intervals. As operating costs rise, the incentive for fleet operators to extend engine service intervals increases. It is critical, however, that extension of engine service intervals does not negatively impact engine reliability and durability since increased repair costs and engine down-time would rapidly offset cost benefits gained by extending service intervals.



At the same time that engine operators are recognizing the benefits for extending service intervals, diesel engine manufacturers are producing updated emission controlled engines with significantly higher specific power output than the older engines they replace. Therefore, operating conditions for engine oils are likely to be more severe due to potentially increased thermal and load stresses. Engine builders and operators also expect improved durability from modern diesel engines, further increasing the performance demands on engine oil technology. Combining a move to extended oil drain intervals with the introduction of engines with higher power densities and longer service lifetimes increases the challenges for developing engine oils capable of providing the level of protection needed to prevent lubricant related engine problems.

The objective of the work described in this paper was to develop a high performance diesel engine oil with the capacity to provide the maximum level of engine protection at extended oil drain intervals.



PRODUCT DEVELOPMENT STRATEGY



The performance benefits of well balanced engine oils formulated with synthetic polyalaolefin (PAO) base stocks have been well documented in the literature (1-4); therefore, this was considered as the preferred approach to develop the best possible premium diesel engine oil. A number of Synthetic diesel engine oil formulations, based on specially developed additive technology, were used as the starting point. The additive components were selected to optimize the heavy-duty diesel engine performance of the final product while maintaining a high level of gasoline engine test performance. For example, the ashless dispersant and metallic detergent systems were carefully balanced to minimize formation of diesel piston deposits. Additionally, the viscosity of the base stock system and concentration of viscosity improver polymer were selected to provide a product meeting SAE 5W-40 viscometrics. This viscosity grade was

considered to be optimum for this application since it allows for exceptional low temperature properties while maintaining the high temperature viscosity at a level typical of modern Diesel engine oils. Some of the characteristics of the resulting synthetic heavy-duty diesel engine oil (SYN-DEO) are summarized in the following section.



Many units have operated on SYN-DEO in heavy-duty, long-haul service at extended oil drain intervals, with some units on drain intervals beyond 100,000 miles. Even under these conditions, SYN-DEO has consistently provided measurable benefits in terms of improved engine performance.

Fleet tests with SYN-DEO are being conducted in Caterpillar, Cummins, Detroit Diesel and Mack engines.



CONCLUSIONS



An SAE 5W-40 synthetic heavy duty diesel engine oil exceeding CG-4, CF-4, CF-2, CF, **, and EC performance specifications has been developed. Results from this study indicate that formulating an optimized high performance additive system utilizing synthetic base stocks provides a product with a combination of unique physical properties, and laboratory and field engine performance attributes. The high level of performance documented for SYN-DEO in standard and extended-length engine tests was further demonstrated in field testing using greatly extended oil drain intervals. The successful performance of SYN-DEO in severe fleet service confirms the potential for premium synthetic diesel engine oils in extended service applications. Application of this technology offers numerous significant benefits to engine

users.



The extraordinary rheological characteristics of SYN-DEO make it well suited for applications where low temperature engine operation or high temperature oil stability are of concern. The outstanding pumping and cranking performance of this product offers excellent low temperature starting performance. At the same time, the synthetic base stocks provide a product with kinematic and high-temperature high-shear viscosities at levels typical of premium SAE 15W-40 mineral oils. Additionally, the high temperature volatility of SYN-DEO is well below that of most multigrade diesel engine oils.



Engine Inspections



Engine inspections after at least 400,000 test miles indicate superior overall wear protection, Piston cleanliness and engine cleanliness even though the oil drain intervals were nominally FOUR times that of the Reference oil.

 

[Mike Ellis]

I am a big fan of "good enough is good enough". Dino oil and the Dodge Cummins recommendations seem reasonable to me, so that's what I use.

 

[illflem]

Mike the only problem following the Dodge Cummins recommendations is that they were determined for your truck with 1997 oil. Oil quality has changed dramatically in the last five years and Cummins isn't about to do tests again just to rewrite a couple lines in the manual.

I feel you can safely double the recommended drain interval on a 12 valve.

 

[Mike Ellis]

Good point Illflem.



So far the only oil-related concern I have regards the filter. On the last change, I switched to the Fleetguard Microglass filter and as the temps have slowly started dropping, I notice that it takes a good bit longer for the oil pressure to build according to the gauge. With the standard Fleetguard, it would hit 40 within a second or so after ignition. With the microglass, it is more like 3 seconds or so. A noticeable difference. Don't know how significant it is, but for peace of mind I intend to switch to a Stratapore filter this weekend.



I recall reading in an older TDR that one of the oil experts recommended sticking with a 15W40 on the theory that it would adhere to the metal better post-shutdown. Makes me wonder a bit if using a thinner oil and more restrictive filter just end up being a wash overall as far as wear, if the pressure is indeed slow building (surely the gauge don't lie eh ) that initial startup could do more wear than thousands of on-highway miles.

 

[Diesel Gunner]

Mike, in fact, about 70% of all normal wear occurs on initial startup. Keep in mind that this is the point at which there is the least amount of oil that is going to be on the cylinder walls, bearing journals, cam lobes and followers, etc. Where the greatest likelyhood of metal to metal contact can occur.



Evidence my little '95 Explorer that I use for work. It has 277 thousand miles on it. The v-6 probably would not have lasted that long if it had been driven irregularly and short distances. I put 1000 to 1100 miles a week on it and it does not get the chance to cool down or drain down between stops each day.

By the way, oil changed abut every 3000, Delo 400 15-40.

 

[Jeff H]

Has anyone read about Sun Coast filters. The big paper towel filter anyway. They ran 300,000 or better by just changing the filter and not the oil. I think they are still running like that with 700,000 miles plus now.

 

[amsoilman]

I recently read an interesting article on Engine oil filtration, I thought some of you would be interested, so here it is.



According to the (SAE) Society Of Automotive Engineers paper 881825, AC Spark Plug and Detroit Diesel Corp. performed a joint study of the relationship between the level of engine oil filtration and Engine wear rates, and found finer filtration reduced the rate of Engine wear.



Diesel and Gasoline Engine wear rates were established by building a Diesel and Gasoline Engine with fully inspected wear components and inspecting them after the test. In both Engines, the upper and lower main bearings, oil rings and compression rings were inspected. In the Diesel Engine, the cam lobe profile and cylinders were also inspected, while the piston pin bushings, piston pins and cylinder liners of the Gasoline engine were inspected.



The total test duration was eight hours. To accelerate wear, 50 grams of AC Fine Test Dust was added, in slurry form, to the crank case every hour.



Diesel Engine wear tests were performed using filters with high efficiency ratings for particle sizes: 40 Microns, 8. 5 Microns and 7 Microns.



Gasoline Engines wear tests were performed using filters with high efficiency ratings for particle sizes of the following sizes: 40 Microns, 30 Microns and 15 Microns.



ANALYSIS



The researchers found clearances in the Diesel and Gasoline Engines varied between 2 and 22 Microns during engine operations. That means particles in the 2 to 22 Micron size range are most likely to damage Engine parts. Particles smaller than 2 Microns will slip through the clearances without damaging bearing surfaces.



CONLUSIONS



The researchers drew the following conclusions:



Abrasive Engine wear can be substantially reduced with an increase in single pass efficiency. Compared to a 40-Micron filter, Engine wear was reduced by 50 percent with 30-Micron filtration. Likewise, wear was reduced by 70 percent with 15-Micron filtration.



Controlling the abrasive contaminants in the range of 2 to 22 Microns in the lube oil is necessary for controlling Engine wear, and “The Micron rating of a filter as established in a single pass efficiency type test, does an excellent job indicating the filter’s ability to remove abrasive particles in the Engine lube oil system.



The smallest particles most popular “full Flow” filters capture with high efficiency are sized 25 to 40 Microns, depending on the filter brand.





Wayne

amsoilman

 

[Vaughn MacKenzie]

Diesel Gunner, racking up miles like that on the Explorer you could have probably done 7500-mile oil changes and still had it running as well as you do now. My first car in the '80s was a '80 Buick Skylark with the 2. 8 V6 which I changed oil every 5000 miles and usually used the cheapest stuff available. I delivered pizza in it, raced it , redlined the crap out of it, etc. It was still going strong at 250,000 miles when I sold it.



One guy I knew (Marty Byrd, Wadesville Indiana) who racked up 1,240,000 miles on his '91 Cummins changed his oil & filter every 10,000 miles using dino oil (Bardahl as I recall). That worked out to once a month and didn't seem to shorten his engine life too much



Vaughn

 

[WadePatton]

read more

I did a meta search for the article that Joe quoted. Here's another article by Jim Fitch.



http://www.practicingoilanalysis.com/article_detail.asp?articleid=401&relatedbookgroup=PowerGen

 

[Ol'TrailDog]

I would add something from the article/test Wade Patton note in the second post:

Here's probably the best known unbiased study, is 22 months and 4. 5 million miles in NYC taxis enough?

Following are excerpt specifically regarding synthetic oil:

One distinction: According to the laboratory tests, Mobil 1 and Pennzoil Performax synthetics flow exceptionally easily at low temperatures - a condition our taxi tests didn't simulate effectively. They also had the highest viscosity under high-temperature, high-stress conditions, when a thick oil protects the engine. Thus, these oils may be a good choice for hard driving in extreme temperatures.



We don't recommend leaving any oil, synthetic or regular, in an engine for 12,000 miles, because accumulating contaminants - solids, acids, fuel, and water - could eventually harm the engine. What's more, stretching the oil-change interval may void the warranty on most new cars.



Even the expensive synthetics (typically, $3 or $4 a quart) worked no better than conventional motor oils in our taxi tests, but they're worth considering for extreme driving conditions high ambient temperatures and high engine load or very cold temperatures.

The cold weather factor in MT and WY is what makes me lean toward using synthetics. at a reasonable change interval.