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Letters to the Editor


Whats a Synthetic Blend?

Dear LubesnGreases,

In his January Letter to the Editor, Paul Buck asked a question of me regarding my companys interpretation of the synthetic blend definition explored by Tom Glenn in his Need to Know columns last fall. Lubrication Engineers would not support the argument that because an engine oil formulation contains 20 percent of performance additive that it would be considered a synthetic blend. The guideline we use is directed by the API Base Oil Interchange Guidelines for passenger car motor oils, which state that up to 30 percent of a Group IV base stock can be used in the finished oil. These PCMOs typically contain between 20 and 30 percent polyalphaolefin, which is our interpretation of a synthetic blend PCMO.

While the additive is indeed mainly a synthetic chemical substance, a significant portion of the additive package in engine oil is diluent base oil which is not synthetic. It is Lubrication Engineers opinion that the end user should be less focused on the makeup of the oil and instead look for superior performance in the application because this is the true measure of a superior lubricant.

Scott Schwindaman

Lubrication Engineers

Wichita, Kan.

Evidence is Clear on SA Oils

Dear LubesnGreases,

Congratulations to Nancy DeMarco on an excellent Publishers Letter in Februarys issue. Hopefully, your detailed evidence of the catastrophic results when substandard lubricants are used for extended periods will awaken some portions of the industry to the dangers of the continued manufacture and sale of API SA lubricants.

Unfortunately, there is a large portion of the consuming population which does not understand the importance of using high-quality lubricants in their automobiles and further does not comprehend the API Service Classifications or the extensive testing required for a lubricant to be able to bear the Service Marks. These consumers buy lubricants based solely on price and give no regard to quality.

We as an industry have to continue and even take to a higher level the struggle which has been going on for many years to make all consumers aware of the importance of using quality lubricants in their automobile engines. As long as there is a demand for cheap SA lubricants, they will be in the marketplace.

Robert B. Portwood

RBP Consulting

Claremore, Okla.

Doing Great

LubesnGreases is doing a great job. It is the singular, most informative source of industry information for my business. Thanks for doing what you are doing.

Jerry Pike

Delmarva Synthetics

Salisbury, Md.

Engine Testing Needs a Clean Slate

Dear LubesnGreases,

David McFalls February column (page 6, Engine Tests and the Field: Do They Match Up?) hits on a topic that sorely needs to be addressed. In passenger car oils, where I have much of my experience, they often dont match up. U.S. Department of Transportation statistics on American driving habits indicate the median passenger car/SUV trip is around nine miles. This suggests many trips are well below this mileage – reflecting all those trips to the supermarket, the kids school, doctor visits, etc. This type of driving generally does not fully warm up the engine, never mind the oil. One of the principal contaminants that degrade engine oil is blow-by, partially combusted fuel from the combustion chamber. Under these driving conditions it never completely evaporates and hence accumulates.

Now compare this with the oil industrys love affair with taxi fleets. Urban taxis typically run very hot. Often the driver never turns off the engine during a shift. This is exactly the opposite conditions of the typical consumer. I would assert that taxi fleet tests are good if you are designing oils for taxi fleets or towing a large RV across the desert.

Gasoline engine sequence tests are relics of 30-plus years of evolution. If you go back to the early 70s you will find Sequence Vs, IIIs, etc. The test descriptions will sound very familiar. Each new iteration was designed to replicate some aspects of its predecessor, and identified by the addition of a suffix letter. This is rather odd, given the evolution of fuel and engines over that time period.

Thirty-five years ago, gasoline was largely unregulated. This all changed with emissions controls. Gasoline today contains no lead, is low in sulfur and must not foul fuel injectors. Yet it wasnt too long ago that we had Sequence IIIE and IID tests running on leaded gasoline. When lead finally was removed from the fuel used in the Sequence III, in version F, initial testing didnt deliver much of a viscosity increase. The engine had to be run much hotter to achieve similar results. Perhaps a New York taxi in August with half its coolant might replicate it.

It has been asserted that piston deposits in some vehicles need this kind oxidation protection. I have never seen this kind viscosity increase replicated in the field. The IIIG is of course much more severe. This suggests that the IIIF/G coincidentally gives this protection.

There must be a better way. The IID was reincarnated as the Ball Rust Test – which essentially replicates corrosion protection for vehicles running on leaded gasoline! It at least eliminated an expensive, pointless engine test.

Why do the oil, vehicle and additive companies persist on this path? There is a real fear that if you radically change the chemistry of the oil there will be field failures. Witness the flap over backward-compatibility in the new ILSAC GF-4 engine oil specification. Also, additive suppliers desire to protect existing manufacturing capacity.

Another engine test with dubious field relevance is the Sequence VIB test for fuel economy, and its predecessors. A good deal of field testing over many years has shown that the only relevant parameter in fuel economy is viscosity. So why do we have this test? In my mind it is designed to optimize fuel economy in the EPA certification testing of new vehicles for federal CAFE requirements. Anyone who has tried to reconcile the sticker MPG with their new cars MPG knows how relevant that is.

The sequence tests themselves have developed their own quirks. Due to the effort to fine-tune them and to emphasize only a couple parameters, such as sludge or oxidation, each is only responsive to those additives that affect it. More simply put, take out all other additives from a candidate oil and it may well pass the test. This makes a farce of some aspects of the additive industrys Code of Practice. If engine test criteria are single-additive-sensitive, it should be possible to develop bench tests like the Ball Rust Test.

The industry should start with a clean sheet of paper that does not have a near-term deadline. Let GF-5, the next generation passenger car engine oil, take its course – but in parallel, rethink the whole testing process. This could lead to better, faster, cheaper specifications. All stake-holders need to be flexible to make this happen.

Mike McHenry

McHenry Consulting

Washington, N.J.

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