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Pour point depressants(PPDs),also know as wax crystal modifiers, are polymeric materials that when added to a mineral based lubricant can significantly improve the low temperature low shear properties or pumpability of an oil. For many years the lubricant industry has set requirements for pumpability of engine oils, with the most well known requirement being the ASTM D4684 MRV TP-1 specification within SAE J300. ILSAC has gone a step further in their GF-4 and GF-5specifications by requiring these generations of oil to be tested for pumpability after severe ageing. As the number and severity of pumpability tests increase the need for proper PPD selection becomes very apparent. This paper will present a brief history of pumpability and the tests used to measure low temperature shear viscosity, including the new ROBO test for aged oils. Data will be presented to show that, with proper PPD selection, an oil can easily be formulated to meet all the low temperature low shear requirements of SAE and ILSAC.