On the Shell Rotella forum, the following question was asked:
Q: Does rotella in a 55 gallon drum go bad after a certain period of time? If so how long?
The following answer was supplied by a Shell Petroleum engineer:
A:There are really two questions to answers about age of oil. Your question regards spoilage. The biggest enemy to long-term storage is contamination. Foreign material – principally water and dirt, will spoil oil. Protect even sealed drums from rain, water, and dusty conditions. Sealed drums “breath”, so a drum stored with openings up can take in water that collects on the drumhead. Another enemy is high temperatures. Avoid long-term exposure in excess of 130 degrees F. Presuming correct storage, oil shelf life is in the neighborhood of five years. To minimize risk, I recommend analysis of oil older than three years. Analyze for physical properties and additive metals content, to assure they are in range of new oil properties.
The second question is old oil’s performance specification. Both engine and oil technology are rapidly changing. Oil four years old today could be only API Service Category CG-4 quality. It would not provide lubrication and protection 1998 and later engines require for optimum performance.
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Follow this link:
http://www.rotella.com/forum.html
Look in the General Discussion forum, around June 3rd, 2002. The reply is on page 6.
For more info about Oil than you or I can handle, the following is a good website:
http://theoildrop.server101.com/ubb/ultimatebb.php
Regards,
Alan