The propshaft is a key part of an automatic vehicle’s transmission and is attached to the gearbox using a propshaft coupling. This coupling is usually a two-piece rubber doughnut shaped gaiter with metal bushings inside that connects the propshaft. The propshaft can be attached to the gearbox using a variety of different fixings such as nuts and bolts or cap screws. The ends of the propshaft can either be parallel or tapered - this will influence which fixing is used.
propshaft failures can happen for a variety of reasons but most common is general wear to the propshaft coupling especially in rubber couplings. If the propshaft coupling becomes damaged it will cause excess play in the propshaft. This play can twist the pipe.
Other causes for damage to the propshaft could be road hazards denting the tube of the propshaft. It’s also possible for the propshaft to shear in half if it has been rubbing against another part of the vehicle possibly through incorrect installation of the propshaft or nearby parts.