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The development of a laboratory test for cavitation erosion corrosion of aluminum pumps with engine coolants is described. It is based on the standard ASTM D2809 test stand but incorporates the pump and cover from a Chrysler 5.9l (360 cu. in.) engine. Operating conditions are varied to simulate components taken from vehicle service. Light duty vehicle service results, obtained in the Colorado Rocky Mountains, for three types of coolant technology with the test pump are presented. Field results include large variations in cavitation protection. Included were two organic acid (OA) coolants, a traditional North American silicate and a European OA silicate hybrid. Comparisons are drawn with the standard ASTM D2809 test, additional components are presented and corrosion morphology discussed.

When compared with new oil, used diesel engine oils exhibited thermal conductivity that increases as the concentration of soot increases. The magnitude of the effect depends on the oil composition, and on the size and dispersion of the soot particles. Although soot in engine oil is generally deleterious to engine performance from the standpoint of wear and deposits, no negative effects were observed on the thermal performance of the oil itself; indeed, even slight positive effects are expected for oils that maintain soot in stable dispersion. Therefore, the thermal challenge for engine oils in diesel engines that use exhaust gas recirculation will be to prevent soot deposition on engine surfaces.