hi robert - i gave up on trying to say something useful on this subject
after my last post, because most people are going to say that the person
who is saying something about it - one way or the other is biased.
i figure that anybody who does the lawn mower test with their own unit
will definitely see a different between synthetic and mineral base -
regardless of brand.
i will shed some light on mobil one since there doesn't seem to be
giving credit where credit should be due.
first, mobil one was developed back in the early 60's and was discovered
by accident. they brought in to the lab where they use to do a 392 hour
dynamic engine oil test. the purpose of this test is to run the engine
for 392 hours solid, then the oil drained, and sent to the lab for
analysis. the synthetic oil sat there behind the door for a couple of
years and when the lab boys ran out of oil to test, they ask about this
stuff that had been sitting there. there was a assigned number on the
box. well, they put the oil in and did the test. when they went to
drain the oil out, it still looked as clean as when they put it in, so
they poured it back into the engine and ran the test again. after the
second time, they did drain it and sent it to the lab with a note of
wanting to know what kind of oil it was. and that's how it came to be.
there were a lot of problems with ester based oils. the amount of type
of additives to put it to make it compatible with mineral oil based
oils. people don't realize what all is put into engine oil. for
example - seal sweller. that's right. it has to be a certain amount to
cause the seal to swell at the same given rate the parts are shrinking
from wear. if you didn't, you was leak more and more oil as the engine
got more wear on it. and that is just one of many. anti foam agents is
another, sure don't want to pump oil around in an engine with air
bubbles in it. after they achieved the final balance it hit the market.
people were highly skeptical of an oil that was advertised that it could
go 25,000 miles without changing. and it was 5 dollars a quart back
then. could change a lot of mineral based oil for 5 dollars a quart.
and then everyone people wrote in about what they put the oil through.
one person owned an airline company and they would send off their oil
samples of their engines to find out when the oil was so contaminated
that it needed to be changed and also based on the metal makeup what
kind of engine trouble to expect. so, they started to send in the
synthetic oil into the lab. the only thing they changed with the oil
filters. it was over 100k miles on the oil before the lab said change
it and with no sign of engine part failure. the lab company was
independent and had no way of knowing what this particular product was.
another person did basically the same thing and at the 100,000 mark, and
when they mike the parts, they were still within original factory specs.
in the late 1960's. the daytona 500 made news. because of the track
temp being around 180 to 200 degrees and the big block race engine was
stuck next to the heat of the exhaust of the car in front of it - that
after the race, when they drop the oil plug, no oil would come out.
they would drop the pan - take a pocket knife and literally cut the oil
out of the pan, rolled into a ball and could bounce it on the floor.
total oil breakdown. the ones that had ran mobile one, not only did the
oil run out of the pan, but when they tore the engine down, they found
that it still have the cross hatch pattern in the cylinder walls. these
stories were carried by popular science and popular mechanics at the
look how long it took for the other brands to finally come out with
their own synthetics and of course, the name of the game is to knock
down the leader. in this case - mobile one.
but they are all the same base makeup, just as all the oil companies use
mineral based oil for their regular oil.
so, which one is best? i'm not going to side up with one of the other.
but, i will tell you this much. synthetic oil is not suited for extreme
high pressure, extreme demand applications, such as use in mining
operations. when you have a 7,000 dollar pump the galls up because of
the type of oil being used, it gets expensive fast. mineral based oil
clearly is the better choice.
but, for light pressure, high temps, hostile environment applications,
such as in autos and trucks, they appear to be the best choice, but it
depends again and the person's driving habits as to whether or not it
would be in their best interest to use them.
i hope this will shed some light on the subject.
knowledge is power - growing old is mandatory - growing wise is optional
"Many more men die with prostate cancer that of it. Growing old is
invariably fatal. Prostate cancer is only sometimes so."