This paper aims to evaluate cohesive properties for an alumina refractory with mullite-zirconia aggregates from wedge splitting tests (WST), and to assess their sensitivity to sintering and testing temperature. Five experiments were analyzed of which four were performed at 600°C. The sought parameters were determined via weighted finite element model updating. The cohesive strength and the fracture energy were successfully calibrated and resulted in simulated data close to their experimental counterparts (i.e., between 4 and 11 times the measurement uncertainty). Increasing the sintering temperature from 1400°C to 1450°C enhanced the cohesion between the mullite-zirconia aggregates and the alumina matrix (20% increase of the fracture energy and of the fracture process zone length). When the WSTs were performed at 600°C, the cohesive strength was 10% smaller while the fracture energy was 70% higher than that at room temperature.