Product Shelf Life
In general, liquid lubricants(not greases) will remain intact for a number of years. The main factor affecting the life of the oil is the storage condition for the products. Exposure to extreme temperature changes, and moisture will reduce the shelf life of the lubricants.
It is important to note that engine/motor oil, and transmission oil industry performance requirements are changing rapidly. The product may be stored three years and still be intact, but may not meet the latest specifications for your vehicle.
As a general rule, the simpler the oil formulation, the longer the shelf life. The following is a guideline under protected conditions:
The following are signs of storage instability in a lubricant:
Water contamination in a lubricant can be detected by a "milky" appearance of the product.
A sign of grease deterioration is the separation of the liquid oil from the solid grease.