Oil, Anti-Freeze and Gear Lube
By Kit Sullivan, The Director of Operations & Training for a 55-unit
chain of quick-lubes and full-service automotive repair centers. He is also
a consultant for the sales and technical side of the quick-lube/ car wash
industry and has about 20 years experience in the automotive lubrication and
repair fields, and holds a 'Master Tech' certification form 'A.S.E.'
All you ever wanted to know about oil for your BOSS 302 (and your
Multi-Viscosity is the way to go. There are two types of lubrication
that motor oil gives to your engine. The first type is called a
'Hydro-Static Boundary Layer'. That simply means the viscosity of the oil,
which is defined as resistance to flow, is what is causing the oil to cling
to the inside surfaces of your engine while the engine is turned off and the
oil pump is not operating. When your engine is first started, this 'Static'
layer of protection will give the engine adequate lubrication for a few
minutes (5 or so) until the oil pump has the ability to create enough oil
pressure to get the heated oil moving up into the upper parts of your motor.
At this point, the second type of lubrication takes over. The oil pump
is forcing the moving oil in between the engine's internal components,
creating what is called a 'Hydro-Dynamic Boundary Layer'. That simply means
oil is moving around by way of the oil pump. With a single-grade oil, the
heat from operation thins the oil that is clinging to the upper parts of the
engine quickly, much more quickly than the oil in the pan. This reduces its
viscosity, or ability to flow and causes the engine to lose its
'Hydro-Static Boundary Layer' of lubrication. Unfortunately, the relatively
thick single-grade 30-weight has not warmed up enough in the pan to be
easily pumped up to the upper-engine before the 'Static' layer is depleted.
So what you have is an engine that has lost its 'static' lubrication, but is
not receiving any adequate 'dynamic' lubrication yet. This creates and
abundance of wear and tear. This is why most engines from the 50's and 60's
would be all used up at around 50,000-75,000 miles. That, and the high
sulfur and phosphorous trace elements in the oil. Multi-viscosity oil nearly
perfectly solves this problem. By starting out at a relatively thin weight,
such as 5 or 10, the oil will be very easily and quickly pumped up to the
critical parts of the engine, creating the 'dynamic' layer of protection
long before the 'static' layer of protection is gone. Through the use of
man-made additives called 'Viscosity Index Improvers' (long chain coil
polymers, which are temperature-reactive), the oil will increase its
viscosity as it heats up to its full operating temperature. Operating
temperature for motor oil is 150 degrees. This 'overlap' of boundary layers
of protection is what has enabled engines to go for 250,000-400,000 miles on
a regular basis, along with much better refined oil. Basically, it has taken
almost all of the wear and tear out of the warm-up phase of engine
operation, which is where 75% of all internal engine wear comes from. All is
not perfect, however: The V.I. Improvers are man-made additives and are VERY
susceptible to the mechanical and very destructive 'shearing' action of the
engine. This 'shearing' action actually tears apart the additive package,
including the V.I. Improvers after a certain amount of time. Driving habits,
engine type and condition make an enormous difference in how long the
additive package will function adequately, but 3 months-3,000 miles is a
good rule of thumb for the typical city and highway driven vehicle. All city
driving (stop and go, idling, etc...) will shorten the oils life
dramatically by as much as 33%. Oil changes every 2,000 miles may not be
excessive under those circumstances. On the other hand, mostly highway
driving at relatively steady speeds on flat paved and dust-free roads is the
best condition for your engine and its oil. This may allow you to increase
the drain interval by as much as 100%.
The wider the range of viscosities on the oil, the less durable and
resistant it is to 'Viscosity Index Breakdown'. For example, 10W-30 oil does
not have as much 'V.I. Improver' as 5W-30, so there are fewer additives to
be broken down by the shearing of the engine. In fact, 10W-30 is by far the
most 'durable' multi-vis oil there is. You should try to stay away from the
wider spreads like 15W-50, 20W-50 and especially the 5W-50.
Also, thicker is not better, no matter what your mechanic or engineer
told you. 20W-50 has 40% more viscosity (resistance to flow) at operating
temperature than 10W-30. This means that your engine has to work 40% harder
just to move the oil around inside your engine. An engine with thick 'oil'
produces significantly less power, uses more fuel, produces more emissions
and runs hotter, all contributing to shorter engine life. A thinner oil can
more easily and quickly be 'pumped-up' to the critical parts of the engine,
takes less energy to move it around, helps the engine to produce more power,
less emissions, better economy. And the engine will last longer too! This
has been proven numerous times in test after test, by many different and
highly respected testing facilities. Unfortunately, the rule that 'you can't
teach an old dog new tricks' prevents many 'experts' from accepting the
facts. Indeed, when I was a kid, it was Castrol GTX 20W-50 in every car I
had! In the years since, I have been working in the automotive lubrication
industry, (15 years now) have been on the engineering boards of several
major motor oil manufacturers. I feel lucky that I was able to 'see the
Indeed, my '71 429 Mustang historically got about 10-11 MPG while it
was run on 'dino' 20W-50. Now that I run nothing but Mobil 1 full synthetic
in everything I own, my Mustang now gets about 17-18 MPG, and runs cooler to
boot! That is significant. Unless your car is an actual bonafide 'RACE CAR'-
no city driving, no idling, no stop and go traffic, no foul weather driving,
etc...- Do NOT use 'racing' oil in your engine. Racing oil has a very narrow
and specific additive package designs for engines that are used in racing
situations, like constant high rpm operation, steady speeds, no stop and go,
no foul weather, etc... The oil that is designed for passenger cars is
immensely more sophisticated than 'racing' oil, only because it has to
function under an almost impossible array of conditions.
If you drive your car on the street most of the time, a good passenger
car, or maybe 'high performance' oil will be much better for you than any
The first number IS the weight of the oil at cold start-up, so a lower
number means a thinner oil that will be pumped up more readily.
The second number is the viscosity (sic) of the oil once it has
reached operating temperature (150 degrees).
The additive 'V.I. Improver' helps it to do the opposite of what it
wants to do when it warms up, which is thin out.
These types of oils are classified as 'non-Newtonian' because of this
5W-30 or 10W-30 is better in colder climes. By the way, the 'W' does
not stand for 'weight', as many erroneously assume. In fact, the 'W' that is
in the S.A.E. designation for an oils viscosity stands for 'winter',
indicating that the oil will flow at its rated viscosity in 'winter driving
conditions', as defined by the S.A.E.
Now, the first number in a multi-vis oil describes its viscometrics at
cold start-up. (engine off for 4 hours or longer, regardless of the outside
The second number describes it performance at operating temperature.
This is where a lot of people get confused.
In a properly running engine with a properly functioning cooling
system, it doesn't matter if you are driving in sub-zero temperature or 100
degree heat. The design of the cooling system will cause the engine &
coolant, and therefore the oil to operate at whatever temperature it was
designed to operate at. So what I'm saying is that the first number is
critical in terms of climate. That is why the 'W'(winter) designation is put
after the first number, not at the end. The second number has almost no
correlation to ambient temperature, only the regulated temperature of the
Now a little trial and error will tell you exactly what weight of oil
will best work in your car.
For the first 500 or so miles after a fresh oil and filter change, the
most volatile compounds of the motor oil will 'volatize' (boil off). This
relatively rapid oil consumption will then taper off into the norm for that
engine. So just top it off after 300-500 miles and then start the 'test':
Make sure that the oil is exactly on the full mark of your dipstick at
'zero' miles of the beginning of the test. Check it at 500 miles, 1,000
miles and again at 1,500 miles. Do not top it off at any time unless it
falls dangerously low. (1 quart or more).
If you find that your engine is using oil at a faster rate than normal
(1 quart/3,000 miles), then try using an oil with 10 viscosity points higher
in the second number.
As an example: start with 10W-30, and at 500 miles top it off. If
1,000 miles later you are a quart or half a quart low, record it and
continue with the test. At 3,000 miles, if you have had to add more than a
quart counting from the first 500 mile top-off, then you should use 10W-40
on the succeeding oil change.
Record your results again. If the 10W-40 does not volatize as readily
then you should stick with that. However, if it still burns away, then try
But, if the 10W-30 does NOT burn off to rapidly, then you should stick
with that. No need to put thicker oil in if its serves no purpose right?
Of course, this is all assuming that your engine is in fairly sound
operating condition. If your engine has worn or bad rings, or worn valve
guides this test will not be conclusive.
And if your choke is not adjusted correctly, you may get a large
amount of unburned gasoline pumped into your oil, which is TERRIBLE for your
engine. Fuel-diluted oil is one of the worst things that damage your engine.
Gas is a solvent, and solvents cut the lubricity of oil-the exact opposite
of what you want. If you can smell gas in your oil (on the dip stick), you
are WAY past due for an oil change!
Synthetic oils, only oils that are made using the 'PAO' method are
truly considered to be synthetic. Castrol Synthetic 'Syntec' is NOT
synthetic oil. It is simply a 'Group II base stock' that has been further
refined using propane de-waxing and severe hydro-treating to give a better
base stock. But is still refined from paraffinic crude, as all conventional
'dino' motor oil is. Although the US FTC allows Castrol to call it
'synthetic', it cannot be labeled as synthetic in Europe. It has a different
name over there.
Mobil 1, Sheaffers, and Royal Purple are all good synthetics.
I stay away from Amsoil for reasons that are far too detailed. OK, I
did not say that there was anything wrong with Amsoil. I just don't like for
personal reasons, and I guess I'll explain why.
Most 'dino' oils have about 20-25% additives, depending on viscosity
and brand. But that figure is almost universal. Motor oil performs five
functions in your engine:
3) Keeps a clean engine clean
5) Protects (w/additives)
As most already know, the crude is refined to whatever degree is
financially reasonable, creating the 'base stocks'. Then the additive
package is introduced to further improve and modify the oils abilities.
The major improvements in refining technologies over the years have
produced very clean and high-quality base stocks, but that is still not
enough. If you could somehow get a hold of motor oil with no additives (like
those produced before 1961) and run it in your modern engine, your engine
would self-destruct in a short amount of time.
So additives are a very important part of the oil.
Here's a shocker: The actual oil in your engine never wears out! It
will always be oil.
There are 3 things that make motor oil unfit for continued use in an
1) The additive package becomes depleted and can no longer offer all
the performance and wear improvements necessary.
2) The oil becomes overly contaminated with particulate matter,
combustion by-products, corrosive acids, dust, dirt, silica (VERY
damaging!), and sludge. The sludge is a direct result of the combination of
heat, air, water and petroleum (which is chemically the reactive trace
elements left in the crude after refining: Sulfur and Phosphorous are the
3) The oil becomes fuel diluted with raw gasoline. Gas does not
lubricate and an oil filter does not filter-out gas. Gas goes right through
undeterred. An oil filter is designed to filter out particulate matter only.
Cars that are driven mainly in the city with a lot of low-speed driving, a
lot of traffic lights, and do a lot of idling tend to put a lot more
unburned gas into the oil. It is common for cars to burn a considerable
amount of oil because it has become fuel diluted, reducing its ability to
lubricate. Then, because the thinned-out oil cannot seal as well, it will
let even more unburned fuel and contaminates past the rings, and more of the
oil will burn away. The gas being introduced will sometimes take the 'place'
of the oil, and when you look on your dipstick, you see that it is 'full'.
This will lead some to believe that their car does not burn oil.
Then, in this example, say you take this car on a 75 mile highway trip
and when you get there, you check the oil only to find out that it is 2 or
more quarts low! This concerns you, because the car has never burned oil
before. So you add a couple of quarts, putting good clean gasoline-free
motor oil in its place with nice and new robust additives. You drive home
the 75 miles at a little slower speeds because you are concerned about the
oil loss. When you get home, you are fully expecting to see a 2 quart loss.
But you are surprised to see that it is still on the full mark! So now you
are confused. Many will blame the brand of oil, the shop who did the change
by installing the 'cheapo' house brand, and some will just scratch their
heads in wonderment. Fuel dilution is the culprit. In reality, the fresh oil
helped to seal well, lubricate better and prevent excess oil loss.
Highway driven cars are not nearly as susceptible to fuel-dilution
problems, as the heat burns the dilution out of the oil.
So anyway, what I am saying is that it is the additive package that
'wears out', not the oil itself. Mobil 1 has about 10-12% additives, far
less than 'dino' oil, because the synthetic base stocks are much, much
closer to 'perfect' and able to do an outstanding job without the use of
nearly as many additives, which can be thought of as modifiers or
'band-aids'. This higher percentage of actual OIL in the Mobil 1 formula
lets the oil lubricate and cool your engine better. That is why engines that
use a good synthetic get noticeably better mileage, run cooler, last longer,
make more power, and produce fewer emissions. But to me, the most important
reason that I use Mobil 1 is because there are no trace elements in it.
None! Remember, it is the sulfur and phosphorous that helps lead to sludge
formation in an engine. Without these trace elements in the oil, the
formation of sludge is remarkably reduced. Engines that are run exclusively
on Mobil 1 stay unbelievably clean and sludge-free. Sludge is far and away
the leading cause of engine failure. That's why I don't like the Castrol
synthetic product: It still contains many trace elements. Now Amsoil
advertises that their oil is the 'extended drain interval' oil. They do this
by pumping up the additive package. They can have as much as 3 times as many
additives as Mobil 1, so in theory it can take more 'shearing', lasting
longer. More additives means less actual oil in the mix, resulting in less
lubrication, less cooling, more wear and tear...you know the rest. The oil
may last longer, but at what price? Your engine? That's not a good trade off
for me. Don't get me wrong. Amsoil is a very good oil, but no matter how
good any oil is, your engine is still going to produce contaminants and
by-products, and the longer they are in your engine the more damage being
I have been involved with motor oil, oil manufacturing and testing,
and additive technology for about 15 years or so. I spent a considerable
amount of time at the Texaco lubrication and additive research and
development facility in the Catskills, which was awesome. They have several
fully computerized vehicle dynos there that can simulate any kind of driving
environment. A few of the dynos are in sealed rooms, and they can add rain,
snow sleet, blistering heat, rough terrain...just about anything you can
imagine, all at the touch of a button from a separate control booth. These
dynos run non-stop, 24 hours a day performing long-term evaluations. Pretty
cool stuff, all in all.
My Sears tractor-mower is about 20 years old, and I have been putting
fresh 10W-30 synthetic in it every 3 months for about 15 years now. It only
holds about a quart. The only reason I switched to 10W-30 syn is because
that is always what I have around the garage. Once I made the switch
however, I noticed that it started much easier, runs quieter and doesn't
seem to get as hot. I have no clue about the B.G.P.G. (Blades of Grass Per
Gallon). Never had a single problem with it, so I guess it's OK. I could be
imagining it, but I don't think so. I try to pay close attention to these
There are a lot of things to consider when it comes to motor oil, to
know the truth. There is so much detailed info to know that the oil
companies know the average consumer would never put forth the effort to
really understand oil, so they don't even try to sell it that way. They just
come up with generic, 1-size-fits-all ad campaigns, so 'Joe Consumer' will
stay just uneducated enough to think that there are really major differences
between brands. In reality, as long as the oil has the 'API' donut on the
back label, nothing else really matters. The front label is totally
worthless as far as a source of useful information. Most of the differences
between brands is in the additive packages, and even then, the differences
are relatively minute, as long as you are comparing similar types of oil
from competing brands. The very best oil out there is not a whole lot better
than the worst, as long as it meets the API and SAE classifications. For all
you guys out there that are looking to use some great oil at a great
price... I have a shocker for you: The oil that Wal-Mart sells under their
house name (Super-Tech) is very good quality oil. In many tests done over
the last year or so, the 'Super-Tech' oil was superior to many name-brand
oils. The oil is supplied to Wal-Mart by Pennzoil/Quaker-State. It uses the
same high-quality group II/III base stocks as their name oil, but uses an
off-the shelf additive package. That doesn't mean it is lesser than the
'Z-7' or whatever additive package they advertise about. Most oil companies
register their particular name-brand additive package formulas, so they
cannot be 'copied' by another manufacturer. That way they can advertise
about 'Nothing is the same as...' and all that kind of crap. An off the
shelf package is available to whatever packager wants to buy it. So it is a
little more economical for the packager. This also prevents stores like
Pep-Boys, Wal-Mart etc. from advertising that their 'house' oil is 'same as
Q/S but at a cheaper price.' Wal-Mart's 'Super-Tech' dino oil is less than a
buck a quart, and their synthetic brand is $2.97/Qt. Great deal. Their
'Super-Tech' oil filters are also very high quality, unfortunately much
better than Fram. Fram has really gone downhill in the last several years,
ever since 'Allied-Signal' bought them. At less than $3.00 apiece, the 'S-T'
filters are a smokin' bargain.
I use Mobil 1 in my real nice cars, and Super-Tech full synthetic in
everything else. And I use Super-Tech filters on everything. I fully expect
everyone who reads this to claim that I am full of beans (or something
else!), and that I don't know what I am talking about. Actually, I do. But,
you know what they say..."You can't teach an old dog new tricks!"
Assuming that you're rebuilt engine is stock or close to it, I would
use a good quality 10W-30 'dino' (conventional) oil until there is about
10-12,000 miles accumulated on the engine. There is a rather complicated
reason for this, but not exactly the reason a lot of guys think.
No matter how well the parts are manufactured, or how meticulous your
engine builder is in maintaining his tolerances, the internals of your
engine still have a lot of relatively 'rough' friction surfaces when freshly
put together. I'm talking about rings, cams, rockers, and bearings...stuff
like that. There is a lot of processes manufacturers put their parts through
to ensure that they have the desired 'hardness' that is required for long
life: Heat treating, 'Tuftriding', things like that. Anyway, for
approximately the first 10-12,000 miles of a fresh engine's life, the parts
all go through a combination of physical and molecular changes. First, there
is a tremendous (relatively speaking) amount of friction on these surfaces
for the first 12K, and the result is that the parts are reaching what
engineers call 'equilibrium'. The parts are wearing into a state of near
perfect smoothness, in relation to each other. Much more perfectly smooth
than any manufacturer could ever produce. Secondly, as this first 12K
elapses the internal parts of the engine are also going through a
'molecular' change (for want of a better word): The best hardening processes
used by manufacturers cannot achieve what the constant heat and operation of
12K can put the parts through. The parts will become even more hardened, and
much more resistant to wear and tear. But they also become more brittle. For
those reasons, it is vitally important that you operate your car in a
variety of driving styles during this high-friction break-in period to
ensure that the internals are fully worn-in, or 'seated' by the time
'equilibrium' sets in. If the parts are not fully worn-in by that time, then
the new-found brittleness will cause an excess of wear and tear, shortening
the engine's life. For that reason, it is a good idea to stick with regular
'dino' for the break-in period, so that you will have enough friction to
wear in the parts, but not so much that you are damaging the engine. Since
there is so much friction, and therefore much more microscopic (but still
damaging!) particulate matter present in the oil, I would recommend changing
it at the first 200 miles, then at 500 miles, and then every 1,000-1,500
miles until you have reached about 12K. At this point, you have done
everything possible to help your engine reach as near a perfect state of
'equilibrium' as possible, and no more break-in is necessary. That means
that now you want to have as little internal friction as possible. At this
point, switch to a good full synthetic. Synthetic lubricates MUCH better
than any conventional oil, which of course reduces internal friction. An
engine that is properly broken in and in good operating condition, and with
fresh fluids in it will suffer practically NO wear and tear for many
thousands of miles. Synthetic also does not have any of the damaging trace
elements in it (phosphorous, sulfur, etc...) that helps to create sludge and
corrosive acids when combined with the by-products of combustion. The
phosphorous, when combined with the remnants of the unburned hydro-carbons
(gas), and then oxidized creates an acid that is chemically identical to
battery acid. This most often leads to premature bearing failure and
excessive cam wear. Since there is more actual oil in a full synthetic
formula, there is more lubrication available to you. Plus, the relatively
'pure' base stocks do not introduce any unwanted elements into your engine.
'P.A.O.'Synthesized oil is made of uniformly medium-sized molecules
that all react in exactly a known fashion. The very small, highly volatile
molecules that are present in 'dino' are what escape past the rings causing
high oil consumption. This is known as 'volatizing'. There are additives in
'dino' that try to prevent this as much as possible. However, these all
contribute to high consumption for the first 500 miles or so after an oil
change as these light weight guys all quickly burn off. The very large,
slow-moving paraffinic (wax) molecules in 'dino' are the ones that stick
together at low temperature, thickening the oil and preventing it from being
easily and quickly pumped to vital areas of the engine. By low temperature,
I do not mean sub-zero. I'm talking about ambient temperature at 'cold
start-up', even in 100 degree outside heat. Additives such as 'pour-point
depressants' are included to prevent this. At high temperatures, 'dino'
oxidizes extremely rapidly. The oil absorbs oxygen right out of the air.
Oxidized oil does not lubricate well, in fact it is thick and gooey, just
the opposite of what we want, right? Keeping your oil at a reasonable
operating temperature is vitally important to prevent oxidation, for at low
temperatures, oil is almost totally resistant to oxidation. Higher
capacities and oil coolers are both excellent ways to accomplish this, as
most already know. All of these things happening in unison often create a
common situation: Oil is used for too long a period and is exposed to
extreme heat for too long a period and becomes overly oxidized, dramatically
raising its viscosity. What started as relatively light weight 10W-30 may
now be a straight 50 weight, all thick, sticky and gooey. This creates
less-than-acceptable sealing performance from the oil, therefore allowing an
excess of combustion by-products to 'blow-by' the rings into the crankcase.
This blow-by introduces unburned fuel into the oil an accelerated rate, and
since gas is a solvent, it cuts the lubricity of the thick, overly-oxidized
oil down to maybe a straight 30 or 40 weight. So when an average consumer
hears that Ford claims his new car can go 7,500 miles between oil changes,
and 15,000 miles between filter changes, he checks the oil frequently to
make sure that the level and condition are adequate. Lets say he checks at
5,000 miles and finds the level acceptable, doesn't seem too dark or sticky,
and assumes that Ford now makes better engines. Wow! In reality, what he was
looking at was heavily oxidized and fuel diluted oil. The fuel dilution
causes the old oil to feel thin and 'oily', not sticky, Plus it gives it a
somewhat lighter color, fooling him. The gas, of course, prevents proper
lubrication, increasing wear and tear. Additionally, the additive package is
all but totally depleted by now, offering none of the long term benefits of
clean oil. Fortunately, ALL of these terrible things can be totally avoided
with frequent oil and filter changes!
A word about synthetics: Only oils that are created using
Poly-Alpha-Olefin based technology are considered to be 'synthetic'. At
least by anyone who knows better. The Castrol 'Syntec' synthetic oil is
actually just a much more thoroughly refined 'dino', coming from the same
crude that all conventional 'dinos' come from. Even though their base stocks
closely approach the performance of PAO synthetics, they still contain trace
elements, and are still susceptible to the effects of temperature extremes
that full synthetics are almost immune to. By the way, Castrol does not make
their own oil. They never have. They don't even own a single refinery. Never
have. They simply buy their base stocks from one of the commercial suppliers
(Coastal-Unilube is one), buy a custom-blended additive package from an
additive supplier, and have a bottler package and label it all for them.
That doesn't mean that it isn't any good. It is very good. But in repeated
testing, the Castrol products exhibit a wide variance in performance, the
results of getting their products from many different suppliers. 'Syntec'
may be good, even excellent oil...but it sure ain't synthetic! The same was
true for Texaco 'Havoline' oil for a couple of years: Two separate companies
were legally allowed to manufacture and distribute 'Havoline' oil. Shell was
one, Equilon was the other. The Equilon-sourced product was far superior to
the Shell-sourced product in every single performance category in repeated
tests. Unfortunately, there was no way for the average consumer to determine
which supplier his 'Havoline' was coming from, for the labels were quickly
changed to remove this information. This is all a moot point now for Shell
is the sole supplier of 'Havoline' branded oil now. I just stick with Mobil
1, and that 'other stuff' I talked about earlier.
Porsche, along with most other European manufacturers typically
recommend extended drain intervals, such as the 15,000 mile interval that
you are talking about. Driving conditions and the typical driver's habits
are markedly different from those in America. The bulk of driving conditions
in Europe is on high-speed highways, with a small amount of city-type
driving. This is the best driving conditions for oil and therefore an
engine. American driving typically consists mostly of city and traffic-jam
driving which is the absolute worst kind of driving. That is why American
manufacturers are slow to come around the same extended length oil drain
intervals as their European counterparts. But they are coming around. The
extended drain interval also allows manufacturers to advertise a lower
maintenance cost to the consumer, which is a powerful sales tool. Of course,
these are under ideal 'normal' driving conditions, which are almost totally
non-existent in reality. That's why there are always 'severe' driving
schedules, or a 'B' schedule in most owner's manuals. As far as the
Porsche's engine using higher quality components and manufacturing? You bet
they do! What do you think you are paying for? But that doesn't mean that
they are indestructible. Remember, when a manufacturer says "Change your oil
every 15,000 miles", they are not claiming that the car's engine will last
indefinitely. They are only claiming that the engine will give good service
for the length of the warranty period. These are usually anywhere from
36,000 to 100,000 miles, but rarely more than that. Any major problems
beyond this point and you are on your own, baby! But with today's technology
and manufacturing methods, ANY engine, even the lowliest Daewoo or Kia
should be able to give good service for 100,000 miles. It just takes
maintenance. 15,000 mile drain intervals will allow an' acceptable' amount
of wear and tear that will not show up in any appreciable way for the length
of the warranty. The key here is that there IS unnecessary wear and tear
being introduced with these extended intervals. What I believe and try to
teach my employees and customers is that with a properly broken-in engine,
regular maintenance (3,000 mile oil changes) and sensible driving habits, it
is very possible to have an engine that basically suffers NO wear and tear
for many, many thousands of miles. The rate of wear can be slowed down to
such a degree that it is almost non-existent. My own personal experience has
borne this out time and time again. My '71 429 Mustang had well over 270,000
miles on the original engine before it was rebuilt. It was still running
fine at that point, no leaking or burning or strange noises, but when I
restored the car, I did not want to put a possibly 'tired' engine back in,
only to have to yank it out at some unplanned future date. When I took it
apart, there were no obvious wear problems. My '79 Lincoln MK-V (400 2-V)
has over 340,000 miles on the original engine and runs perfect. No leaks,
knocks or noises. Does not burn oil. And since these engines are known for
being underpowered and thirsty, but certainly NOT known for being
durable...this is really a testament. 3,000 mile oil changes are recommended
for the sake of preventing wear and tear. 15,000 mile oil changes are
recommended for the sake of slowing down the wear and tear. Another
consideration for the manufacturers is that the various world governments
are urging them to use less and less oil products whenever possible. The
extended drain intervals are one way to help achieve that. The problem we
are all facing is the upcoming adoption of the new 'GF-4' classification of
motor oil. The A.P.I. (American Petroleum Institute) adopted a
classification system to rate the performance of motor oil back in 1961. For
gasoline burning engines, it uses letters and the first letter is always an
'S', signifying that it is for 'Service Stations' (remember those?),
assuming that a service station would only be adding oil to gas-burning
engines, since no one ever believed there would be diesel powered cars at
that time. I always found it easier to think of the 'S' as standing for
'spark ignition', which is how a gas engine works. Anyway, the first letter
is 'S', and the second letter denotes the performance characteristics of the
oil through the use of additives. 'SA' oil was introduced in 1961. Every
time the oils required performance was improved, the second letter was
advanced. We are currently at a level of 'SL' for new vehicles sold today.
This is a superseding system, meaning that every newer performance-grade oil
can be used in any application that called for a lesser grade. e.g...today's
'SL' rated oil can be used in a 1995 vehicle that originally called for an
'SG' rated oil. And that older car will derive extra benefits from the newer
oil that were not available when the car was new. However, an older 'SG'
rated oil CANNOT be used in today's cars that require an 'SL' rated oil. By
the way, it is highly unlikely that anyone would ever be able to
accidentally find or buy any outdated motor oil considering that motor oil
is a fast moving commodity. It just doesn't sit on the shelves for too long!
This is where the 'GF-4' fiasco comes in. The government requirements
of upcoming oils performance are so stringent, that simply improving the
existing formulations will not be sufficient. The main culprit is
phosphorous. The phosphorous content in motor oil and gasoline is the main
contributor to catalytic converter failure. Today's requirements are that a
properly maintained catalytic converter must perform within its design
parameters for a minimum of 50,000 miles, and they are designed to do so.
When this requirement was put into effect (1974), vehicles lasted an average
of 75,000 miles or so. The idea was that as most of the cars converter's
started to fail, they would be heading to the junkyard anyway. With today's
vehicles traveling 200,000 miles regularly, the government feels that the
50,000 mile minimum is inadequate for long-term protection of the
environment. So they raised it to 150,000 miles, beginning with the 2005
model year. The only way that this is possible is for the phosphorous
content in motor oil to be reduced by 50% from what it is currently. The
problem is that it is not possible to refine conventional 'dino' oil using
the methods that are currently in use by refineries and make oil that is
sufficient for this. It must be refined using a different method, (read:
expensive) and the big problem is that neither one of these oils will be
compatible with the opposite vehicle's applications. That means that there
will be 2 totally different type of oils for the consumer to choose from.
Well, the oil and vehicle manufacturer's have lobbied hard, and have won a
small concession: Instead of 'GF-4' having 50% of the current levels of
phosphorous, current refining methods can reduce it by about 30% maximum,
although it will still cost more. The benefit however, is that it will be
compatible with all standard 'API' as well as 'GF' classifications. So one
type of oil can satisfy both standards. This will only be short-lived,
however, as part of the agreement for the 30% reduction for 2005, is that by
2008 'GF-5' will be the requirement at the original 50% reduction. Whereas
the API set the standards for American vehicles performance, and the
European and Japanese counterparts set their standards, this is the first
time that all three of these organizations have gotten together to set a
'world' standard. This 'world' organization is called 'ILSAC' (International
Lubrication Standardization Acceptance Committee), and you will see this on
the back of almost all current motor oils.
Let's see...blended oils.
The oil companies found out that by adding a small amount of synthetic
base stock to conventional 'dino' stock, they were able to significantly
increase its cold and hot temperature performance. It approaches
full-synthetic performance, but is still a ways away. (Blended oils are
almost a definite with GF-4/5 oils). They are significantly better than
regular 'dino'. However, there are still the trace elements in the 'dino'
portion of the oil, and that is what contributes to sludge formation. For
that reason, I do not use blended oils. Blended oils use anywhere from 2% to
5% synthetic base, depending on viscosity and brand. None are higher than
5%. (Most erroneously assume it is 50/50). This is a BIG moneymaker for the
If your BOSS is overheating, or just running hot when you are at a
'cruise', there are several things you can do to help it 'cool off'. My 429
CJ did the same thing. First, I would say use 10W-30 synthetic oil. Make
sure your cooling system is 'up to snuff'. Are you running a 50/50 mix of
anti-freeze and water? Here's why I ask: Anti-freeze is 10 TIMES heavier
than water! If you are running a 50/50 mix, your engine is working 5 times
harder just to move the coolant mixture around than if you were running
straight water. Of course, water is extremely corrosive, so you cannot run
straight water, right? Put only enough anti-freeze in your system that will
get it to the lowest temperature you expect it to reach. I live in Florida,
so I only run 8 ounces of anti-freeze in mine. I also added a can of
water-pump lubricant/anti-corrosives (very important!). Lastly, I put in two
bottles of redline 'Water Wetter'. This breaks up the surface tension of the
water, making it easier for the engine to move the fluid around. And I use
distilled water, which does not have the heavy mineral content that tap
water does. It's only about a buck a gallon at the grocery store. All of
this has resulted in an almost 20 degree drop in temperature, on average.
This really helped me, and a couple of my friends had good results with this
The statement that 'synthetic' lubricants are 'too slippery' in
reality does not make any sense: The more slippery a lubricant is, the
better it lubricates (generally speaking).
The reference to the 'lack of adhesion' from synthetic lubricants is
really just a reference to two other functional properties of the fluid:
1.) 'Viscosity', technically defined as 'resistance to flow'.
This is a measurement of how easily a fluid will flow away from a
static point. Thicker (higher viscosity) fluids resist this to a greater
degree, so they tend to 'stay put' a little better.
2.) In a gearbox such as a differential or a manual transmission, the
only type of lubrication that you get is a 'Hydro-Static Boundary Layer',
which simply means that there is no mechanical or pressurized mechanism for
'forcing' the lubricant in-between the moving parts. (Other than the
rotating action of the components themselves, which is not anywhere near
If there were insufficient boundary layers of lubrication between the
gears in a diff or a manual tranny, then the internals of the gearbox would
'weld' themselves together relatively quickly. That's no good.
So there is a complex group of additives to address just this
predicament, and it is called 'E.P'. The additives that make up 'E.P.'(which
stands for 'extreme pressure', natch!) are developed from zinc, copper,
brass, and other chlorinated solvents. These are commonly referred to as the
'yellow metals', and they possess some very desirable properties. They have
a very low coefficient of friction, and they tend to 'stay-put', which makes
them very resistant to the gearbox's attempts to remove them from contact
surfaces through the mechanical shearing action of the component in
Basically, no matter how much pressure is applied to these additives,
they cannot be 'squeezed' out from between the contact surfaces. This is
what allows gear oils to lubricate so effectively without any type of
This may bring up a couple of questions amongst the more curious:
First, if 'E.P.' is that good, how come it isn't put in motor oil to provide
even better protection when the engine is first started, or if you were
suddenly to lose oil pressure? Great idea, but it can't work for a couple of
Mostly because it is not legal for the additive to be put in motor
oil, because chlorine and any chlorinated solvent or derivative is
considered to be a carcinogen, so it can't be in there. The thinking is that
a portion will escape to the atmosphere through normal combustion and
exhaust, and the government says no!
Transmissions and gearboxes are considered to be 'sealed', so the same
rules do not apply.
Also, when a chlorinated compound is combined with the normal
by-products of combustion, it creates an acid that is almost chemically
identical to battery acid! This wreaks havoc with bearings and such. In
fact, before this was illegal, there were chlorine-based additives in motor
oil, and they had a terrible effect on engines. That is why most engines in
the 50's and 60's would give good service for about 60-75,000 miles, and at
that point they would be 'smokers' and 'knockers'. Basically, land fill
By the way, it is not legal for the manufacturers to put EP in the
oil, but there is no law that says YOU can't put it in your own oil, if you
would ever want to.
EP is the active ingredient (hidden through clever chemical
'copyrights' on the labels) in many 'engine treatments' available out there.
Specifically, 'Dura-Lube' is loaded with it. Stay away from that
stuff. Or, if you use it, just make sure you change your oil at least every
3 months regardless of the miles! At least that will keep the harmful acids
from forming so quickly.
Did you ever wonder why 'Slick 50' or one of the other 'engine
treatment' companies didn't market their own brand of motor oil with their
product built right in? Well, because they are not legally allowed to.
Slick 50 tried to get away with selling oil filters with the product
already installed, but they had to pull those from the market pretty
So, as long as the gear oil you are using is of the correct viscosity
range, has the correct EP and LS (limited slip) additives in it, then
synthetic is in all respects a better choice than any dino lubricant.
C - 16.5 This product was originally developed for engine oils
Sure is a lot of "stuff" in there, I lost focus many times.
But I don't think I saw a thing about the lack of zinc in the modern
formulations, nor lifter wear on flat lifters. I think it can be
safely assumed that many of that 427's 270,000 miles were on older
formulations with higher zinc?
And it sounds like Castrol, amongst others is recognizing a problem
with the modern oils in older engines.
Oh, and sorry for the spelling in the header..been working on a lot of
Swedish cars lately!
1963 8E5 Champ (Champ 6)
1995 VW Passat (Vanilla..yuk)
1994 Volvo 850 (Tilley)
1973 Volvo 1800 ES (Hyacinth Bucket)
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