WAYPOINTS ALONG THE ROUTE LIMITS OF THIS INVESTIGATION You should keep in mind that this investigation is limited to the equipment that I own and to oil I have purchased. That limits the conclusions to results obtained from my Cummins 6BTA5.9 diesel engine and two Honda gasoline engines. The oils are limited to Mobil Delvac 1 SAE 5W-40 in the Cummins and Mobil 1 SAE 5W-30 in the Hondas. We all realize that all engines are not created equal, and I suspect that all synthetic oils are also not created equal. I do have knowledge about the quality of my engines because I have experience with them. I don't have any experience with the synthetic oils and can make no judgment about the difference in quality, if any, between the different brands. A more definitive investigation would include more engines and more oil brands. NEW POA READING - THE PLOT THICKENS You may remember from Synthetic 002 that the first Mobil Delvac 1 I purchased had a rating of API CG-4 and the first POA reading was 0.6 after 1260 miles of moderate to full-load operation. After that initial reading, the oil was changed to Mobil Delvac 1 with the current API CH-4 rating. Since then additional readings have been made on the Cummins and Hondas. Here are the updated POA Readings. The last readings for the 6BTA5.9 and the Hondas are the new readings. POA Readings Units will be h for hours and m for miles. Oil Type code: S = synthetic, P = petroleum based. Engine m/h m/h POA Oil Oil Bypass Read Type Filter Accord 93: 53,834 initial engine miles 56m NA 2.0 S 375m NA 2.0 S 818 m NA 2.2 S Accord 99: 6,234 Initial engine miles 41m NA 0.0 S 287m NA 0.8 S 856m NA 1.4 S 140 Ford ADC: 629 initial hours 162h 0 1.2 P 172h 10 0.25 P 182h 20 1.00 P 197h 35 1.10 P ... 468h 306 1.40 P Northern Lights 8K: 220 initial hours 116h 0 0.3 P ... 187h 71 0.9 P 6BTA5.9: 52,150 initial miles 1,000 0 1.1 P 1,330 330 0.4 P 1,810 810 0.9 P 2,330 1,330 1.0 P ... 22,318 21,318 2.2 P 1,260 1,260 0.6 S 416 416 0.6 S The range of readings for synthetic oil is twice that of petroleum-based oil. That means that a reading of 1.0 from petroleum-based oil is equivalent to a reading of 2.0 for synthetic oil. The 6BTA5.9: The only difference in the last two readings is the change from Delvac 1 API CG-4 to Delvac 1 API CH-4. Note that with only about a third of the mileage (416 miles to 1260 miles), the POA readings are the same with the API CH-4 oil. Does this mean that the CH-4 does, indeed, have a better detergent package? I think it does. The Two Hondas: Note carefully that the POA readings on the Honda 99 are catching up with the Honda 93 with amazing acceleration. It is most interesting to me that this has happened in only about 800 miles on each engine. The readings after the next oil drain are going to be most interesting. I think it means that the synthetic oil continues to do a better cleaning job on both engines than petroleum-based oil, and I expect that the readings on these engines will become similar after the next oil drain even though the Honda 93 has more than five times as many miles as the Honda 99. But the answer to that question is why this investigation is going on. In other words, this is why we play the game. Differences: Note the dramatic difference in the readings between the 6BTA5.9 with a Gulf Coast Filters bypass-oil filter and the two Hondas without any bypass-oil filters. Because the 6BTA5.9 is a six-cylinder diesel and the Hondas are four-cylinder gasoline engines, I would expect the POA readings to be higher on the 6BTA5.9. This is especially true because the diesel operates under greater load than the Hondas. I can only attribute the differences to the bypass-oil filter. All of these issues will become clearer as we get more readings. But it is safe to say, even at this initial stage, that something is going on with the synthetic oil that did not go on with the petroleum-based oil. Next week CaptnWil leaves for a two-week trip that will put the Cummins under load again for another thousand, or more, miles. Readings from that trip will be interesting. MORE AUTOS USING SYNTHETIC OIL My Son-In-Law owns a BMW and his owner's manual requires synthetic oil to be used. He gave me the BMW 800 customer support number. You already knew that CaptnWil called it to get the whole story. Well, synthetic oil is not required, but since 1997, all BMW engines have been shipped with synthetic oil from the factory. In addition, synthetic oil is used by BMW dealerships for all refills. I was advised that if repair of the engine is required, engine warranty will be in question if synthetic oil is not used. This was somewhat vague, but the point was that BMW expects all engines since 1997 to use synthetic oil. BMW has a part number for their own synthetic oil and approves two others, Mobil 1 and Valvoline SynPower. BMW is the first engine manufacturer I have discovered that requires, or almost requires, synthetic oil in their engines. My daughter owns an upscale 1999 Volvo, and the dealership insisted on changing to synthetic oil at the first scheduled oil drain. A call to their 800 number produced absolutely no information on this issue. They told me to check with my local Volvo dealer service manager. You already knew that was unproductive. These two items don't prove anything about the superiority, or lack of superiority, of synthetic oil, but they are interesting facts. It does indicate to me the possibility of the beginning of a trend. While the major diesel engine manufacturers, who are of greatest interest to us, don't require synthetic oil, or even recommend it over petroleum-based oil, they do approve it and even sell either full synthetic or synthetic-blend oil. Caterpillar even has Mobil Delvac 1 relabeled under its own name. IT FEELS DIFFERENT Synthetic oil on the hand feels different than petroleum-based oil. The synthetic oil clings to the hands in a way that petroleum-based doesn't. No matter how you wipe your hands, you can feel the film of synthetic oil on your hands until you clean them with hand cleaner. The feeling is quite unusual and almost unpleasant. It feels as if all the air is excluded from your skin, and you are in a hurry to get the stuff off. I have no idea how this relates to what it does in the engine. MORE WAYPOINTS ALONG THE WAY We'll get to additional waypoints in time, but different from those we normally chart, we don't know the Lat/Lon of the next waypoint yet. That, however, is the way of a "Work In Progress." CaptnWil, Ret 40 Pier Pointe New Bern NC 28562 (252) 636-3601 captnwil@coastalnet.com