Nanofluids have received much attention due, in part, to the range of properties possible with different combinations of nanoparticles and base fluids. In this report, we measure the viscosity and thermal conductivity of suspensions of graphite particles in ethylene glycol as a function of volume fraction. Above the percolation threshold, the slope the thermal conductivity enhancement reduces, while that of the viscosity enhancement increases. These results provide insight into the mechanisms behind the variable viscosity.