Reprinted from the Action News July 2004
Many motorists today are confused. For several years General Motors, BMW and Mercedes-Benz have been installing monitors
on their dashboards that light up to indicate when it's time to change oil. GM monitors have frequently allowed motorists to
drive 5,000 miles and as much as 7,000 miles or more before signaling that it's time to change oil. The Mercedes-Benz
service system indicates 10,000- to 20,000-mile oil change intervals.
Naturally, this flies in the face of the 3,000-mile drain recommendation that oil companies insist are necessary to
What's a Car owner to do?
Petroleum oil companies have insisted that their oil needs to be changed every 3000 miles, even for these vehicles with
the dashboard light. But the world's largest automaker, General Motors, states that oil change intervals should not be based
on miles driven, but rather on driving style. In a feature story titled "Supersize Me! GM moves to extend drain intervals,"
(May 2004 Lubes N Greases, vol. 10 issue 5) David McFall unveils the latest move in GM's strategic plan to cut loose
The GM solution is for motorists to depend on their patented Oil Life System (OLS). The owner's manuals in today's GM
fleet no longer make specific mileage recommendations at all. Instead, the GM Oil Life System analyzes the engine's
operational data including temperature, revolutions and speed, to calculate the rate of engine oil degradation and determine
when an oil is nearing the end of its life. At this point a message on the dashboard signals that it is time to change
Each OLS computer model is engine-specific because GM believes each engine behaves differently under the various driving
situations and conditions. Driving styles vary as well. The OLS allegedly calculates all factors pertaining to both the
engine and the driver and thereby makes its oil change recommendations.
According to GM senior project engineer Robert Stockwell, who has been studying analyzed oil samples from vehicles with
OLS, "In all cases where the OLS signaled for an oil change it was before the oil was worn out." And how long were the drain
intervals? "Many of these samples," said Stockwell, "were from vehicles with greater than 10,000 miles on the oil, a few
with more than 14,000 miles and at least one with 16,000 miles. These intervals were recorded in vehicles using regular
mineral oil. Synthetic oil gets even longer oil change intervals."
Let There Be Light
Long before the issue of OLS and extended drains hit trade magazine editorial radar screens, AMSOIL began to zero in on
this opportunity for Dealers. The theme of extended service life with AMSOIL synthetic motor oils has, of course, been a
feature of the company from the beginning.
Despite the clear environmental benefits of extending drain intervals, the major oil companies dug in their heels. For
more than three decades the message of regular, frequent oil changes has been sold to consumers and the mechanics who
service their vehicles. Millions, if not billions, of dollars have been spent on advertising and training to reinforce this
"change your oil every 3,000 miles" mantra.
In February of 2003 AMSOIL published an article directly targeted to the impact oil change indicator lights were having
on drain intervals. "Oil Monitors Revisited" (National Oil & Lube News, Feb. 2003) combined observation, internet
research and first hand comments from a GM powertrain authority to shed light on the philosophy behind the Oil Life Sensor.
At the heart of it all, GM does not believe in recommended drain intervals. GM believes in the oil sensor logarithm,
developed by Dr.Shirley Schwartz and tested over many millions of miles of service.
A month later, in March 2003, David McFall of Lubes N Greases chided the oil industry for keeping drain intervals
shackled at three thousand miles when they knew that longer drain intervals were completely realistic. In a column titled,
"Drain Intervals: How Long Must We Wait?", McFall held up AMSOIL as an oil company that was "unshackled."
This year, McFall turned his attention to the OEMs themselves, focusing on "the light," that is, the GM oil change
indicator light. Clearly GM has unshackled its oil change indicator and soon there will be 24 million more cars on the road
relying on the Oil Life System.
QUESTIONS AND ANSWERS
Now that General Motors has broken away from any mileage recommendations, how are AMSOIL Dealers to instruct their
customers when the light goes on?
At the end of the day AMSOIL still recommends oil change intervals based on miles. Just as General Motors has done
extensive testing on their algorithm in order to feel confident in its recommendations, AMSOIL likewise has done extensive
testing regarding its motor oils. It should be noted that GM set up its system based on typical conventional motor oil.
Synthetic motor oil can go further, as GM has indicated.
How should Dealers respond when their customers see the "change oil" light go on?
When customers are using AMSOIL 25,000-mile oils, AMSOIL recommends that the oil be continued in service and that Dealers
help their customers learn how to reset the dashboard light. This is a simple matter of consulting the owner's manual or
contacting the local GM Dealership. If customers have installed XL-7500, they can feel confident going 7500 miles or six
months, whichever comes first. If the light goes on at 4500 miles, the same instructions apply as above: reset the
What if they are using XL-7500 and the light does not go on for 11,000 miles or more?
If the oil light doesn't come on until after 7,500 miles, the customer can choose to change the oil and filter or keep
going until the change oil light goes on. AMSOIL XL-7500 is a premium oil that is fully capable of meeting the needs of GM
cars in accordance with their recommendations. You can always feel safe using the XL-7500 oil until the light comes on.
The Demand For Better Oil
A second trend that is simultaneously occurring today has to do with emissions. For a number of years the automotive and
oil industries have been grappling with the problem of meeting increasingly stringent emissions standards. The result of
this governmental pressure on OEMs is that oil companies have been forced to reduce additive content in order to increase
catalyst life. Catalysts are the element in the catalytic converter that reduce the bi-products of combustion in the
internal combustion engine.
There are trade-offs, however. First, when additives that provide wear protection are excluded, the result is the
potential of increased wear. Second, oil companies must wrestle with the matter of backward compatibility. That is, when oil
formulations are altered, can they also be retrofitted to older car models? Finally, today's smaller, hotter engines present
new challenges as well.
As you would expect, AMSOIL synthetic motor oils address nearly all of the problems brought on by these changes. The
problem of increasingly hot engines is solved by synthetics because they reduce friction and, consequently, the primary
by-product of friction, which is heat. Even in the presence of heat they are oxidatively stable.
As GM progressively extends drain intervals and promotes the environmental benefits of extended drains, the AMSOIL
message will become increasingly mainstream and the 3,000-mile drain interval message will be further eroded. Eventually
every automaker will follow suit, not only for environmental reasons but because consumers are busier than ever and frequent
oil changes have always been a hassle. Why, with vehicle manufacturers recommending drain intervals longer than 3,000 miles,
would customers trust an oil that an oil manufacturer recommends be changed at 3,000 miles?
Ironically, the two needs of modern motor oils are contradictory. On the one hand, motorists want oil to last longer and
require fewer oil changes. On the other hand, governmental pressure on OEMs is forcing motor oil companies to reduce the
amount of anti-wear additives in motor oil to keep emissions in check with the result that oils cannot be counted on to last
AMSOIL is already well positioned for both of these performance expectations. Testing is currently underway with new
formulations that will keep AMSOIL ahead of the curve, no matter how steep the expectations become. And for the 200 million
cars currently in circulation today, AMSOIL synthetic motor oils remain the best value and offer the best protection money
Ultimately, no matter what the oil light says, GM recommends that if the light hasn't gone on in one year, the oil and
filter should be changed. A new idea? Not really. That is a message that was stamped on the first can of AMZOIL Super
Premium 100% Synthetic Motor Oil over thirty years ago. We were first then, and the competition still hasn't figured us
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