LaBr3:Ce scintillators have excellent properties, such as energy resolution, time resolution and efficiency. However LaBr3:Ce performances have been investigated only for small or medium volume crystals. We investigated the properties of a large volume 3.5″ × 8″ LaBr3:Ce crystal and we compared them with those measured for smaller detectors. The 3.5″ × 8″ LaBr3:Ce crystal was coupled to a HAMAMATSU R10233-100SEL photomultiplier and with a custom-made active voltage divider. In this work we have studied pulse lineshape, energy, and linearity in the energy range 5 keV (the average L shell binding energy) up to 22 MeV (from a (p,γ) reaction). In addition the stability of energy estimation as a function of count rate (2 kHz - 250 kHz) was also measured.