An experimental study on heat transfer enhancement in an automobile radiator using Al2O3/water-ethylene glycol (EG) nanofluids is carried out. Heat transfer enhancement studies can help in the design of lighter and more compact radiators for the same given load, which in turn can improve the fuel economy of the automobile. A closed loop experimental setup is designed using a commercial automobile radiator for the study. The effect of adding EG to water on the overall heat conductance (UA) is studied using two mixtures of water-EG proportions, 90:10 and 80:20 (by volume). They showed a reduction in UA by 20% and 25% respectively. Experiments have also been done using Al2O3/water-EG nanofluids. The nanofluid was prepared using an 80:20 mixture and 0.1% (vol.) of Al2O3 nanoparticles. The addition of nanoparticles enhanced the heat transfer performance by 37 %. All the experiments have been conducted at a constant coolant flow rate and coolant inlet temperatures varying from 40 o C to 70 o C. The results showed that the heat transfer performance of the radiator reduced with the addition of EG and increased with the addition of nanoparticles to the water-EG mixture.