The answer is simple: Yes!, But only in high temperature applications.
Grease is a combination of a base oil and a thickener. As a bearing warms, the oil becomes available to lubricate the bearing. If a bearing becomes excessively hot, the oil will become less viscous and will separate from the thickener. At these extreme temperatures, the oil can run out of the bearing leaving only the thickener behind. This leaves the bearing with inadequate lubrication.
A high temperature grease does a better job of preventing oil separation at higher temperatures. This type of grease is a better choice for bearings that run hot. Examples could be bearings in conveyor ovens or in heat treating operations. If a regular grease was used in these applications, the oil would separate, the bearing would loose it’s lubrication, and damage would occur.
But what happens if we use a high temperature grease in a bearing at “normal” operating temperatures? The base oil in high temperature grease would not become available for lubrication at “normal” temperatures. Therefore, a high temperature grease would not be the proper choice for a bearing operating at “normal” temperatures.
“High temperature” is a relative term. Greases are available in low temperature, normal temperature, high temperature, and extreme temperature formulations. Temperature ranges of these different types of grease vary by product. The proper grease should be chosen based on the grease manufacturer’s temperature recommendations.
Every condition found in the field is unique. Rules of thumb and best practices described here may not work in all situations. We recommend consulting an engineer or lubrication specialist for advice on your specific situation.