# Oil Life Monitor Erratic After Cruze In Storage



## 6speed (Dec 7, 2011)

In early spring, I put my Cruze into storage for 13 weeks. It was not driven or even started up during the storage period. When I put it on the road last month, the Oil Life Monitor (OLM) dropped significantly, to the tune of 24% Life Expectancy-almost 2% per week-all while the engine was never started up.
Now for the baseline & the little game I play. Since I use Full Synthetic Dexos oil, I aim for just short of 10,000 miles per oil change. At each 5% drop in Life Expectancy, I record the odometer reading. It is close to 510 miles driven for each 5% drop (about 102 miles per 1%). I have data on every oil change on this car. It was very predictable. Another thing it does- now it only changes on a startup, it used to change while you are driving-you could watch it.
Now that it is being driven daily again, the predictability is gone. I’m monitoring it closer, every 1% instead of 5%. The computer is doing its own thing in showing Life Expectancy. Each 1% drop is anywhere from 175-300 miles driven. Our other late model GM car that goes into storage (usually 6 months at a time) has never exhibited this when it is put back on the road.
The old “normal” program before the Cruze storage was so predictable, in a future post, I’ll show my data. To me it looks like the computer uses a cyclical program based on miles driven ONLY in making it drop each 5%. Nothing to do with counting engine revolutions, engine starts, temperature, or driving style like people say.


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## XtremeRevolution (Jan 19, 2012)

Oil oxidizes as a function of time exposed to the elements. Group 3 "synthetic" oils are a tad better than conventional oils but still have a limited life of about 3-6 months. Certain oils have more robust anti-oxidant additives, but those eventually deplete, at which point the oil oxidizes. Oxidation is a fancy word for "sludge." Oxidation occurs due to both time and heat, although the heat required to oxidize oil is pretty high, such as what you have inside our turbo and in our piston cooling jets. The DEXOS1 specification requires a minimum NOACK volatility of 13% due largely in part because of this issue.


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## Jim Frye (Mar 16, 2011)

Maybe I missed it, but did you change the oil after the storage period? Also, what were the storage conditions? Detached garage, insulated garage, outside under a cover, etc? Was the battery disconnected during the storage period?


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## 6speed (Dec 7, 2011)

Jim Frye said:


> Maybe I missed it, but did you change the oil after the storage period? Also, what were the storage conditions? Detached garage, insulated garage, outside under a cover, etc? Was the battery disconnected during the storage period?


I did NOT change the oil when the car went into or out of storage. Stored in an unheated detached garage(early spring to summer conditions). Battery was always connected during storage period.


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## obermd (Mar 3, 2012)

Change the oil and filter and reset the OLM.


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## 6speed (Dec 7, 2011)

Have 5K to go to next oil change. Will see how it goes when I clear the OLM.


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## 6speed (Dec 7, 2011)

When OLM went to 50%, the phony program is back to "my normal"(about 102 miles per 1%). Did not need to clear to get it to act as before car went into storage.


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## spacedout (Dec 7, 2010)

GM uses many unknown variables in the OLM, from the description of what you say is going on it seems how long the oil has been in the car also has some effect. 

Its always been my understanding one should change the oil before storage or after to remove any build up of acids or condensation.


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