No i don't believe anything of the sort. The color of the oil indicates
the color of the oil. The question I ask is why do you care if someone
else prefers not to have a certain color oil?
Actually that is not exactly true. There is a remote possibility that
those particles could become harmful to the engine. For instance if you
are tooling down the interstate and you head gasket lets loose and
suddenly it dumps a bunch antifreeze into your oil. That will very
quickly use up all the dispersant/detergent additives in the oil. That
means the particles that were happily being held in suspension doing no
harm will start to rather quickly precipitate and agglomerates into
larger particles and that can cause harm. Fresh clean oil can absorb
more antifreeze before engine damage occurrs than old black oil can.
Saying extended oil changes are safe is based on the assumption that
the engine is always going to be functioning properly. Keeping the oil
cleaner than it needs to be can be insurance against certain types of
malfunctions such as when excess fuel, antifreeze or dirt get dumped
into the oil unexpectedly. Those may not be likely occurrences, but they
do happen. Also, the older dirt laden oil is much less able to maintain
it's viscosity and shear properties if the engine overheats excessively.
And in this day and age excessively overheating engines is probably the
number one cause of lubrication failures. Blow a radiator hose and the
temps inside an engine can very quickly exceed 250C.
If someone changes their oil often enough so that it doesn't get black
they never have to worry about whether they have reached the point where
the additives can no longer protect the engine from the dirt. For
instance if someone has a half a dozen cars, maybe its just a lot
simpler and safer to change the oil when it starts to get very dark
rather than keeping detailed records for so many vehicles.
But who cares if you happen to change the oil before you absolutely need
to? I mean you probably don't wait to eat until you reach the point
where it adversely affects health. You probably pea a lot more often
than you really have to. Many people don't wait till April 15 to file
their taxes. Doing things before it is absolutely positively necessary
is pretty common human behavior. The question is why is this one
particular behavior the one that gets so many people agitated?
Sorry for jumping in in the middle here, but it appears to me that you're
suggesting that the bad effects of a blown head gasket can be mitigated by
clean oil. That's a huge falacy.
If the head gasket lets go, it won't matter if the oil was changed 10
minutes or 10 months ago. The contamination of the coolant into the oil is
the least of the problem when the head gasket goes.
Well I'm sorry but the SAE doesn't share your opinion. There have been a
number of studies on levels of antifreeze contamination on oil and its
No not really, in terms of immediate consequences contamination of the
oil can be the only real concern. A small amount of antifreeze lost from
the cooling system won't impact on the engine temp and if the coolant
leak is from the water jacket into crankcase then the only short term
consequence at all is the contamination of the oil.
That is not to say you can't create a scenario of head gasket failure
where it doesn't matter how old the oil is. Even if it doesn't matter
most of the time, that misses the point. The point is that no matter how
improbable it may be it is possible to have just the right kind of leak
with just the right amount of leakage that whether the oil is old or
fresh can make a difference. So anyone who tells you there is no
possibility that the fine particles suspended in the oil, that
accumulate with miles, is going to ever cause harm is simply not being
accurate. The best you can say is that it is unlikely they will ever
Your entire reply is very difficult to understand, is filled with negatives
stacked upon negatives, and appears to my faulty brain to be pretty much
Should that head gasket let go in juuust the right way, in juuust the right
place, and you're looking at...
I'm not sure the age of the oil makes much difference here.
Try reading it slowly - it isn't that complicated.
Well you seem to decipher some of it just fine. The age of the oil isn't going
to prevent a leak if that is what your thinking was said.
The point was the age of the oil can make a difference in some situations.
A fairly small amount of glycol added to dirty oil can do damage where that
same amount added to engine with fresh oil can avoid the damage. One of the
consequences of adding the small amount of antifreeze is that it will rob from
the dispersants and detergents their power to hold fine particles in
suspension. That won't matter as much if the oil is not very saturated with
The point is it is inaccurate to say there is zero risk to storing the fine
particles suspended in the oil. You can if you want debate how small the risk
Obviously watching US TV has reduced your reading skills to very low
I'll put it in terms that even a simpleton should be able to understand.
"These minute particles pose no danger to
your engine, but they cause the oil to darken."
I responded that although that holds true most of the time there can be
unusual circumstances where those fine particles do cause harm.
The link Dr. Beam provides indicates a 10,000 mile oil change interval
It goes on to say "Mileage can be extended furthest in gasoline
engines by using higher quality motor oils containing a high total
base number (TBN)."
So anything less than 10,000 miles between oil changes is recreational
and unnecessary according to the OP.
Not 2000, not 3000, not 5000, not 7500 miles.
Hey, all, let's re-argue detergent vs. non detergetnt motor oils, plus
single grade vs. multigrade? I cannot believe I'm still seeing this same
old crap argued so fervently in 2010. I've lived (and driven) thru all
Nowadays I drive an '03 Accord sedan w/5AT and I send an oil sample for
analysis every spring. 2010 will be the first year for an annual oil
change. Just for the record, 6,300 miles since I changed the oil in
05/09). Analysis reports show my non synthetic oil as well as I4 engine
are in excellent condition. I do some things non-factory: change oil
filter every oil change, change engine air filter (along with the cabin
one) annually, etc.
My $.02, YMMV, of course, and we're all entitled to our opinions. :)
when i posted this - i was thinking of the people that do what their
granddaddy did, even though combustion technology, fuels, oils and
engine metallurgy are dramatically different these days. i was hoping
to enlighten, but i guess i'd forgotten just how rigidly proud some
people are of their ignorance and ability to keep their head stuck
firmly in that sand.
next time you get sick, doubtless you're going to resort to burning
camphor and bread poultices. those "doctor" people and their
new-fangled "technology" and "drugs" clearly don't know what they're doing.
Well, if someone else paid for the oil analysis I wouldn't mind
running the oil until the magic numbers said to change the oil.
I like my mom's Buick, the computer tells her when to get the oil
changed. It didn't tell her to get the manifold gasket changed that
started leaking but I'm sure GM is working on a sensor for that.
well, he "changed" oil by adding when it was a quart or two low.
Jim, you never enlighten, you issue directives.
generally, drug researchers don't make unqualified long term claims
based on short term tests.
let me put it another way; you'd have to be an idiot to believe you
can project the results from a year test on fleet vehicles to 10 years
or more of normal passenger car use. not to mention folks in cold
country are rightfully skeptical of tests conducted in CA.
are you familiar with engineering personality disorder?
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