A centre bearing on a propshaft serves as a crucial support, enabling the rotating propshaft to have a bit of flexibility. This helps reduce vibrations and noise by acting as a stable pivot between the two segments of the driveshaft. It’s commonly used in vehicles with longer wheelbases, where the shaft is divided into two parts. Essentially, it plays a key role in absorbing any misalignment between the transmission and rear axle, ensuring the shaft rotates smoothly.