This thesis work is the result of a 7 months engine testing and calibration activity performed at the ICEAL (Internal Combustion Engine Advanced Laboratory) inside the Energy Department (DENERG) of Politecnico di Torino. The experimental study was headed by ICE PhD students research team, with the supervision of Prof. Stefano D'Ambrosio, and it involved test bench investigation of an industrial diesel engine provided by FPT Industrial (F1C) with a modified design for PCCI (Premixed Charge Compression Ignition) advanced combustion mode. The aim of this activity is to gain insight on the influence of the utilization of cooled and uncooled EGR strategies on performance and pollutant emissions characteristics of the above-cited engine, with focus on the attainable benefits that hot EGR could produce on the common shortcomings of PCCI combustion.