The propshaft coupling is rubber or metal doughnut shaped ring which forms a two-part connector that’s used to connect the propshaft to the gearbox on an automatic transmission. Various types of propshaft couplings can be used to connect the propshaft to the gearbox, but the more common of them are clamps or axial keys. The propshaft coupling can be either flexible or fixed. The ends of the propshafts are often parallel, but sometimes the ends of these are tapered and this will influence the type of propshaft coupling used.
If there is a problem with a propshaft coupling, you will most likely hear a vibration under acceleration. The propshaft itself will also feel loose with excess play being a major issue. You may also hear a clunking noise if the damage to the coupling is more severe, which could be caused by unnatural movement of the propshaft. In the case of rubberised propshaft couplings wear can be caused due to the material they are made from. Over time, the rubber will heat and be subject to general wear which will eventually cause them to crack and become damaged.