In the present work, the effect of nanofluids on convective heat transfer performance in a radiator will be experimentally analyzed. Results of property measurements and numerical predictions suggested that water based nanofluids have the potential to provide enhanced cooling performance compared to pure water being used in the automotive engine cooling system. Based on literature review, there is lack of experimental data in this area, which is of importance for validation and analysis. Therefore the present study aims to fill this gap by experimentally investigating the heat transfer performance of TiO2-, SiO2- and Al2O3-water nanofluids on engine cooling system, at volume concentrations ranging from 0.1 to 1%. The experimental setup includes an Aprilia RXV 450 engine and a radiator. Thermocouples and resistance temperature detectors (RTDs) are placed at the inlet and outlet of the radiator in order to monitor the air and coolant temperatures. A flow meter is attached to the radiator hose in order to determine the flow rate of the coolant. The coolant flow rate will be varied from 1 GPM to 3.5 GPM by controlling the engine rpm and the experiments will be firstly conducted with water as the coolant. The prepared nanofluids will then be used as coolants for testing and the heat transfer data will be collected once the experiment reaches its steady state condition. The tests will then be repeated with 0.1%, 0.5% and 1% volume concentration of different nanofluids. The results will be collected with and without nanoparticle seeding conditions, and the impact on performance will be analyzed and compared with the predicted results.