Choosing the right grease and ensuring its compatibility is crucial for machinery performance and longevity. Currently, no reliable field test exists for grease compatibility, so it's safest to assume two different greases are incompatible. Greases vary in base oils and thickeners, impacting their properties and applications. Mixing incompatible greases can lead to altered consistency, compromising lubrication and causing increased friction, heat, and wear on bearings, risking equipment failure. Always clean bearings and housings thoroughly when transitioning to a new grease. Consulting lubrication specialists or manufacturers can provide valuable guidance on grease selection and compatibility to maintain optimal equipment performance.