Originally Posted by Fifty150
Your Ford is suppose to be 5,000 miles, with synthetic blend 5W-20. If you changed oil every 2,500 miles, you would not hurt your car. If you used conventional oil for 10,000 miles, well; according to Kendall, NY taxis can run that for 100,000 miles.
We need real science. Real confirmed, validated data. Not theoretical mathematics based on used oil analysis of a random sample of the population. If someone, anyone, could start with every make and model available, run those cars in a controlled testing environment, replicate the results with consistency, then publish findings.......Somebody else's UOA on their Subaru, with whatever combination of oil & filter, couple with the UOA of a 15 year old Toyota using a different combination of oil & filter; has nothing to do with your Dodge K Car; which you are living out of. Okay, well, maybe it's me. I live out of a Dodge K car, but that's nobody else's business.
I want to see some science. I want to know, based on replicated testing with consistent results. I want to see how a full synthetic oil is better than generic conventional; where they handicap the outcome. In a Crown Victoria, used for severe duty fleet service, Ford recommends a synthetic blend, to be changed every 3,000 miles. How would the engines look if they followed OEM specifications?
We know that Kendall kept the engine fairly clean for 100,000 miles. Which is maybe not a big accomplishment considering that today's vehicles easily go over 100,000 miles, and that should be possible using any full synthetic oil.
Here is where I read between the lines. The conventional oil in the testing, was changed every 10,000 miles, and the engine ran 100,000 miles without catastrophic failure. Nobody here would drive 10,000 miles on conventional oil, but the testing showed that it can be done, and the car kept running.
There are three things syn lubes are really good at:
1) providing less pumping resistance and better flow capabilities at cold temps (really cold; like below -20F ambient).
2) providing generally longer sustainable OCIs due to oxidation resistance and viscosity retention (typically only appreciable well past 15k miles)
3) separating a fool and his money
Pretty much all lubes today are far more capable than folks can conceive of or admit to. I routinely ran 10k mile OFCIs in my 4.6L MGMs, and had done so for years, on conventional oils. Both cars are in my son's control now, but they are both still running; one with 130k miles and the other with over 260k miles. The UOAs always show great wear control, low contamination, etc. Under valve cover visual inspections show no ills of sludge. And all this has been achieved on the cheapest of API certified lubes; RK house brand. I have run studies using info from both macro and micro data sets. I have run my own experiments comparing syns to dino fluids. (UOAs available here on BITOG).
There is really good data to show my assertions are valid and correct. I don't know what you mean by "We need real science ... Not theoretical mathematics based on used oil analysis ..." What is it that you believe would be proof other than large sample sets for macro data, and large amounts of data from within a micro study?
I do statistical process quality control for a living; written many DOEs and studies for HALTs, etc. I have over 15,000 UOAs in my database from a very large set of applications, from all manner of uses and environments. Could you please elaborate on your "want to see some science"? What is it specifically that would convince you of something, one way or another?
