The present invention utilizes simple dimethylsilicone fluids of the proper viscosity/molecular weight added to modify the low temperature properties of polycyclic hydrocarbons. One preferred embodiment of a polycyclic hydrocarbon is a perhydro dimer of alpha-methyl styrene. Addition of the dimethylsilicone fluid to the perhydo dimer of alpha-methyl styrene improves the low temperature performance without degrading the requisite low shear stress shear strength properties. Low viscosity dimethylsilicone lubricating fluids combined with polycyclic hydrocarbons are suitable for use in infinitely variable transmissions providing good low temperature flow properties and high shear strength at high temperature and low contact stress conditions.