Re: shelf life for 2 stroke oil?
Most engine oils will have a shelf life of about 3-5 years. Oils with heavier additive packages, or insoluble additives, will have shorter shelf lifes. Ideally stored oil will be free from sunlight, moisture, extreme temperature changes, and will remain unopened.<br /><br />Signs of storage instability will include settling out of the additives, or a goo or gel at the bottom of the container, floc or haze, precipitates or solid material, color change or haziness, and a milky appearance as a result of moisture.<br /><br />There are two types of "shelf life". Type-1, or nonextendible and Type-2, or extendible. Most oils are extendible. That is, upon specified visual inspection or laboratory testing, the shelf life of the oil can be extended if it passes inspection. Nonextendible shelf-lifes will have an expiration date, and are not to be used past that date.<br /><br />Some oils/fluids are packaged with nitrogen in an attempt to rid the oil of oxidation and to extend shelf life. Most consumers use oil before shelf life becomes an issue, as oil specifications change rapidly and new, better oils are constantly being produced to meet the demands of new engines.
