In today's world it is not good enough to put in the ‘specified' lubricant without knowing who specified it and why. One of the first steps in any lubrication program is determining the machinery's lubrication requirements. This is the combination of researching the original specification (generally from an OEM manual); understanding how your equipment operates in the manufacturing process, as well as the environmental conditions the machine is exposed to.
The OEM manual will provide general guidelines for the lubricant, such as the type of lubricant required and the viscosity. The viscosity is usually generalized to the ISO viscosity grade at several ambient temperatures. The OEM guidelines are adequate for most machines in regular service but do not usually take in account temperature extremes or other environmental considerations. With knowledge of the machine components being lubricated, and the use of lubricant viscosity-temperature charts, and if necessary, the assistance of the OEM Application Engineer the lubrication needs can be determined for each individual machine.
Tip Provided by Kristopher Sonne