Vehicles manufactured after 1990 often have differential housings sealed with RTV. Over time, extreme vehicle vibration and even rough roads can cause the RTV bead to break. If the bead breaks and the vehicle loses the axle lube, the transmission gears begin to rub and wear. That's the whining sound that you hear. Unfortunately, it's a repair that needs immediate attention. Fel-Pro offers precut differential replacement gaskets for these applications, so you won't have to worry about applying RTV and waiting for it to set up to seal. In addition, installing precut Fel-Pro gaskets helps to eliminate the risk of contaminating the differential housing with RTV. Fel-Pro replacement precut gaskets eliminate the need for RTV.