This paper describes a new test-rig designed for investigating wear and friction in a conformal conjunction such as journal bearing. Tests have been carried out with this rig to investigate the possibility of replacing mineral oil based lubricants used in turbines in hydro-electric with new more environmentally adapted synthetic ester based lubricants, with or without additives. The lubrication regime under test is boundary lubrication in a highly loaded sliding contact subjected to an intermittent motion. Temperature and linear wear (displacement) have been monitored. The test results show no significant difference in wear rates or levels between the mineral and synthetic esters. The synthetic esters are characterised by higher friction coefficients than mineral oil; especially after running in where the mineral oil lubricated bearings show a decrease in friction. This running in behaviour was only observed when mineral oil was used. The predictable behaviour of the esters indicates that there is a strong possibility to replace mineral oils with more environmentally adapted lubricants