GM'S Change Engine Oil Light

Use Amsoil And You Can Extend This

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 protect engines.

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 "Super size 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 drain intervals. 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 oil. 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 oil 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 power train 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.

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 reduced, 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.

Dealer Opportunities
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 as long. 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 can buy. 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 AMSOIL Super Premium 100% Synthetic Motor Oil over thirty years ago. We were first then, and the competition still hasn't figured us out.


Q Now that General Motors has broken away from any mileage recommendations, how are AMSOIL Dealers to instruct their customers when the light goes on?

A 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 in 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.

Q How should Dealers respond when their customers see the "change oil" light go on?

A When customers are using AMSOIL 25,000-mile oils, AMSOIL recommends that the oil be continued in service and that the 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 instruction apply as above: reset the light.

Q What if they are using XL-7500 and the light does not go on for 11,000 miles or more?

A 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.

Amsoil Action News / July 2004

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