I was wondering if anyone knows with certainty what factors are used in
the oil life indicator. Obviously, mileage or cumulative RPMs is one of
them. But I would think that there are others like temperature, total
engine running time, and maybe length of time since the indicator was
last reset. I'd be interested to hear if anyone knows for sure.
Things positively known:
- RPM speed/duration
- idle time
- engine temperature
The OLM does NOT measure the oil directly; that is to say, it cannot
detect how "dirty" the oil is, nor can it tell the difference between
dino or synthetic.
Please, follow my advice: use synthetic and change your oil every 5,000
miles, regardless of what the OLM says.
But what is that advice based on? I use dino oil (or really whatever
synth-blend is currently offered) and change my oil every 7000 to 7500. At
165,000 miles, my Accord is still going strong.
Changing synthetic every 5000 won't hurt anything on a mechanical level, but
it sure takes away a good deal of economical value by shifting the expense
to over-frequent oil changes.
It's based on nothing useful. I have a 2003 Accord 4-cyl. I switched to
Amsoil 0w30 at 40,000KM after what I call an initial breakin period. I
replace the oil filer every 20,000KM. I replace the oil every 40,000Km.
Amsoil has just recently come up with nano-filter technology that will
allow me to replace oil filter every 40,000KM. My second break in
period is just occuring. I have 223,000KM. I am now getting the best
possible fuel consumption of 5.9l - 6.1l per 100KM while driving 100KM
per hour. My oil consumption is exactly 0.6l + whatever's in the oil
filter per 40,000KM. I recently bought a 2006 Pilot. It has a life
indicator that shows or "reduces" the expected life of the oil the
higher the sustained engine rev is. I managed to get it to a 5% of life
left in just over 5500KM. However, I use Amsoil 5W20 (for inital engine
breakin of 40,000km)which at that mileage is visibly very clean, so all
I've done is reset the oil life indicator and continued with the same
oil. The best thing for the society is to inform themselves about
engine oil and mechanical durability. It will save a ton of money and a
pile of resources for the whole planet. The rest is scare tactics and
oil industry capitalizing on everyone's ignorance.
Hope this helps.
Based on what? Are you saying that you have put more research into this
topic then Honda's engineering team has?
Your advice sounds like little more than a repetition of conventional
wisdom. Usually what "everyone knows" is at best incomplete and often
While I understand your hesitation to follow my advice blindly, I
assure you I have spent countless hours researching the topic. I do not
agree that a 5,000 oil change interval is "too frequent"; I reserve
that statement for those 3,000 OCI fanatics. Honda's OLM is very
liberal on oil life because they pride themselves in "low cost of
ownership". After 5,000mi on conventional oil, the EP and AW additives
in the oil break down and the engine is running on a minimal level of
protection. The Molybdenum/Phosphurous content settles out of
suspension, and the engine may utilize ZDDP (a zinc additive) as its
last line of defense against metal-to-metal contact. When the oil is in
a weakened state, varnish begins to form; if you go even further,
sludge becomes a serious issue. While a 7,500mi OCI is okay for the
average cost-sensitive consumer, it is unacceptable to car enthusiasts.
A synthetic blend is not a good way to go. It is just regular oil with
synthetic additives, making up about 20% of the total volume. You
should either stick to conventional oil (for lower cost and near-equal
performance) or full synthetic (for superior protection). I highly
recommend Mobil 1 full synth or equivalent. I am also against boutique
synthetic oil companies, such as Redline or Amsoil; their prices are
nearly double the average synthetic for a small increase in
performance. It is totally unnecessary unless your engine will be
seeing race conditions.
Also, I should point out that there is no solid evidence that synthetic
oils are capable of lasting much longer than conventional oils. Many
companies sell "15,000mi OCI" oils because they have complete faith in
synthetic products; however, most industry professionals agree this
extended OCI concept has not yet been proven. The same additives used
in dino oil are used here, and they break down at about the same rate.
Synthetic has better cleaning abilites and viscosity stability at high
temps due to a lab-made base stock, but it's no miracle product for
your engine. Save your money and get the standard full synthetic.
http://www.bobistheoilguy.com and its forum,
http://theoildrop.server101.com are excellent places to learn about the
subject. There are many misconceptions about engine oil and its
capabilities, so learn up and buy smart.
And yet none of what you say takes any REAL WORLD factors into account. How
about at what percentage the oil spends at optimum operating temperature vs.
"warming up"? Someone who takes many short trips, hardly ever completing
warm up will "spoil the oil" much faster (i.e. in less miles) than someone
who drives many highway miles in a single trip. The first person spends say
10% at operating temperature while the second spends 90% at operating
temperature. This is a MAJOR factor and yet you don't take it into account
at all when you give a BLIND recommendation of "change oil every 5000
miles". To not take all the factors that oil life depends on into account
is total bunk. Even the Honda manual, before the oil minder computer system
at least gave 2 major scenarios. Normal and severe driving. The oil life
minder takes the rest of the important factors that you choose to ignore
To give a recommendation without knowing all the factors is like pulling
numbers out of air. Yeah, 3 or 5k is a safe guideline that will hurt
nothing but ones wallet. But to give a REAL guideline (what the oil life
minder systems is programmed to do) many factors are required. You want to
piss extra money away, go for it. But try not to tell other people how to
spend their money unless you factor in all the variables, otherwise it's
advice no better than the fortune card you get at the carnival for $.25.
Blind recommendations? Carnival fortunes? Such eloquent criticism, for
a car forum. I apologize if my advice was offensive; I'm only sharing
the information I've learned about oil through personal research. But
of course, you're free to spend your money as you please. I can't see
why you're so angry over a stranger's suggestion to learn more about
Alas, I must present my rebuttal: I am accounting for "real world"
factors when I discuss oil; it's the oil companies that cite ideal
conditions when they advertise the capabilities of their products, in
the vein of traditional marketing techniques. While I do agree that
there is no single oil change interval that works for everyone, 7,500
miles will wreak havoc on an oil regardless of the severe or normal
conditions it's put through. While it's true that a person who spends
most of their time in stop-and-go traffic and short trips will need a
more frequent OCI, the 5,000mi interval is a nice round number that
will accomodate all (but race) conditions. There is nothing Honda
states about oil life that I've "ignored"; I only choose to supplement
it with more research. Car manufacturers take into account that the
average driver knows very little about cars, and much less about engine
oil. This is why they included the OLM on their newer models; they
don't expect consumers to educate themselves on the application of oil
for their particular scenario.
Like I stated before, the 7,500mi OCI works for a person who considers
their vehicle as a tool to take them from one place to another. In the
end, it will translate into lower maintainance costs, which is a big
plus for those with shallow pockets. However, if you compare a Virgin
Oil Analysis to a Used Oil Analysis of the Honda OEM oil, you can see
the stages of degradation that occur. I believe Honda ranks as one of
the greatest engineering firms in the world, but they adjust their
vehicle market to suit the average person. Check out the link I posted
before, and you can learn some more.
I also disagree with your statement that a 5k OCI has no benefits, and
only drains money. It's true that it's a considerable increase in cost
(especially using synthetics), but it all comes down to how much you
care about your vehicle. Judging from your statements, I doubt you took
the time to learn about the value of a UOA; it can show you the "real
world" statistics that you so crave. You're thinking like a shopper,
not an enthusiast.
My suggestions are passionate because I care about my vehicle to the
point where money is no object. If you feel the tradeoff in costs are
not worth the added protection, then you should stick to what you think
is best. All I ask is that you educate yourself before placing all your
faith into a single belief.
And yo continue to ignore other factors such as trip duration which directly
affects at what operating temperature the oil spends the majority of it's
useful life at which directly relates to the length of it's useful life.
The "stages of degradation" occur at DIFFERENT rates for different people
due to driving habits practices and conditions. None of which can be
addressed in a general guideline.
I didn't say it has no benefit. It will have benefit for someone who drives
many short trips with their oil spending very little time at operating
temperature. I did state that it will be a waste of money for people sho's
oil is allowed to get to operational temperature and spend most of it's use
I have educated myself and you have chosen to ignore my entire point. My
point is that there is no "magic number" in regards to oil life/mileage and
that it will vary from car to car based on use.
"But try not to tell other people how to spend their money unless you
factor in all the variables, otherwise it's advice no better than the
fortune card you get at the carnival for $.25."
Seems pretty demeaning to me.
"While I do agree that there is no single oil change interval that
works for everyone, 7,500 miles will wreak havoc on an oil regardless
of the severe or normal conditions it's put through. While it's true
that a person who spends most of their time in stop-and-go traffic and
short trips will need a more frequent OCI, the 5,000mi interval is a
nice round number that will accomodate all (but race) conditions."
OCIs can't be addressed in a general guideline? What do you think car
manufacturers have been doing before the invention of the Oil Life
Meter? You stated yourself, they recommend two different mileages based
on normal and severe service.
You haven't looked at http://theoildrop.server101.com , have you?
No, it's my opinion and was said/typed with zero anger.
Ah, so there is a difference! But 7500 is very easy for a highway car to
acheive. Cars and oils are better today than they were 30 years ago.
Progress. Even the 5000 mile interval can't be trusted as a general number.
What about the person who hardly ever drives and it takes 2 years to acheive
5000 miles? For those people, time is a bigger factor than mileage and once
again the "raw number" is not appropriate.
Yup, it's called progress. Many years ago people peed in a small vessle
they kept under their beds cause it was easier than trudging to an outhouse
in the middle of a winter night. Then technology brought us indoor plumbing
and the chanmber pot disappeared.
Now we have computers that take ALL the factors affecting oil life into
consideration and thus the 3000 OCI of old has morphed into "change the oil
when the computer says to" with a stage of "here are some different
intervals based on use" in between.
It's a web forum no different than this newsgroup other than it's using HTTP
instead of NNTP.
> Now we have computers that take ALL the factors affecting oil life
This is part of my argument: the Oil Life Meter should NOT be
considered the end-all be-all indicator. Like I said, they are very
liberal on oil life because of the "cost of ownership" concerns. Honda
wins that category in many car magazines (especially the Civic and
CR-V), so they are very conscious of the issue.
Also, I thought we were talking about Honda's Oil Life Meter the entire
time. It measures oil life in percentages; they recommend oil to be
changed at 15%. Another reason I don't trust it is because my car sees
the rev limiter very frequently (8,200 rpm) and I have been at 6200mi
when the OLM reads 20%. I often drive fifteen minutes or less (small
town), so one would assume the large number of cold starts would wear
out the oil faster. That was the first red flag that made me think
twice about the meter.
Repairs due to maintenence are part of the "cost of ownership" equation.
Part of why they wil in that category is by not breaking down as much thus
requiring costly repairs.
What does it matter who's oil life meter we're talking about? They all may
be a little different from each other, but they will all take more factors
other than just mileage into account.
If you weren't hitting the rev limiter, the meter might have shows 30% at
6200 instead of just 20%. That means it's working as it should looking at
all the factors.
You want to change your oil earlier than recommended, go ahead. My entire
point in this thread has been that blanket advice without using all the
factors is bunk. And when people give advice that differs from others they
will be challenged on it. You could go ahead and change your oil at 1500
and I won't care. When you recommend others do the same despite changes in
modern engineering (i.e. engines are better, oil is better and we have
better ways of predicting it's condition), someone will challenge that
Not much of what I said has stuck with you. No way would I ever
recommend changing oil regularly at 1,500 miles; that is an inexcusable
waste of oil and money. Maybe it's worth it if you drive your car once
a year, or twenty hours per day. Granted, a car with it's oil changed
every 500 miles will last much, much longer than a car with oil changed
every 7,500. It's an issue of ethics; hopefully, no one is that
desperate to become an enemy of the environment.
I welcome opposing opinions, it gets a good discussion going. So here:
Engines are "better", yes; advances in technology allow tighter
tolerances, hotter temperatures, and more complex moving parts without
risk of failure. This puts even more strain on engine oil, and car
manufacturers can do this because they know that the easily available
motor oils on the market have improved and can handle this. But the
only major improvement in engine oil is the quality/price of synthetic
oil since its first appearance in the seventies; traditional oil
companies have changed their additive packages (sometimes up to three
times a year), but their base stock hasn't improved. In fact, most oil
companies don't create their own stock, but buy it from other well
established companies in bulk. Pennzoil buys stock from Mobil 1, for
instance. Group IV and V stock is superior to anything on the market,
but the *endurance* of the oil has still not been proven to last longer
than dino oil. Thus, engines have become tougher on oil, and while
non-synthetic oil has improved greatly in the area of extreme
pressure/anti-wear additives, the advances in oil longevity are
negligent! This is why most car companies have been suggesting the
3,750/5,000mi service interval since the eighties, and still do,
regardless of using dino or synthetic.
At some point, more frequent changes add no further life to
the engine. That point may very well be around 3000 miles
per oil change (with a commensurate time limit).
I think there is no basis (data, common sense, or otherwise)
for saying an engine will last "much, much longer" the more
often one changes the oil.
I would agree.
In fact, a change every 2,500 miles including the filter will suffice
for even the most poorly rated motor oil.
Use of Castrol or Valvoline dino oil should easily be good for 5,000
miles with maybe an filter change half way in between.
I don't really see a great advantage with synthetics for engine
lubrication but in transmissions/differentials, they can make a
considerable difference in performance and extended length of service life.
Actually there has been testing which seems to show that wear metals per
mile rate decrease as oil continues in service.
One independent effort:
There are other industry studies about this, but they cost money to buy.
Actually, the home study you reference appears to have used
data on a single car and for only a few samples of oil
total. I wouldn't recommend anyone waste a moment slogging
through it and figuring out whatever point the authors seem
to be trying to make. They seem to be amateurs at best.
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