Development of a Reliable Extreme Pressure (EP) Screening Test for Tractor Lubes

The need has long existed for a reliable bench test to measure the load carrying properties of multipurpose power transmission fluids for tractors. This paper describes one that meets this need. The test utilizes an SAE Load Machine, modified for oil recirculation and temperature control, and runs under low speed, high torque conditions that simulate final drive operation of tractors. It was used to predict performance of several experimental multipurpose power transmission fluids in actual tractor gear tests, and a good correlation was found. The data provided demonstrate that this test is a valuable tool in formulating improved multipurpose power transmission fluids.