The objective of this investigation was to develop a test method for measuring the resistance to rotation of a ball bearing, caused by the grease in that bearing, as a function of temperature. Low temperatures were of particular interest, and it was desired that the test results be expressed in terms which could be used in mechanism design by proper correction for bearing size, etc. It was also desired that the method be capable of measuring 'break away' as well as the running torque of a bearing filled with grease.