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"Called Mobil today and asked what the shelf life was. He told me that the oil in their original containers can last up to 5 years assuming it's in a controlled environment, ie no sudden temperature changes."
Also direct from the manufacturer. And here is a controlled study result which (though rather vague) is enough to convince me that storing conventional oil cold is a bad idea. Need more info on synthetic.
"Regarding cool whether gel formation, a small except from SAE j300 1999:
4. Because engine pumping, cranking and starting are all important at low temperatures the selection of an oil for winter operation should consider both the viscosity required for oil flow as well as cranking and starting, at the lowest expected ambient temperature.
Pumping viscosity is a measure of an oils ability to flow...during the initial stages of operation. Test in ASTM D 4684. ....samples are tested after a slow cool cycle. This cycle has predicted as failures several SAE 10W-30 and 10W-40 oils which are known to have suffered pumping failures in the field after short-term (2 days or less) cooling. These field failures are believed to be the result of the oil forming gel structures that result in excessive yield stress and viscosity of the engine oil...
A.2.1...After preliminary warming, the sample is subjected to a controlled temperature/time cycle over 5 1/2 to 7 days. The cycle reproduces ...instability or reversion which has occurred during storage of oils in moderately cold cyclic conditions. Recent work shows relevance to engine oil pumpability failure. Oils exhibiting pour reversion have solids resulting from wax gel formation, at temperatures significantly higher than their ASTM D 97 pour points.
Extracted, from ASTM D 4485-03 Standard Specification for Performance of Engine Oils, copyright ASTM International, 100 Barr Harbor Drive, Wets Conshohocken, PA 19428, USA."
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