The tailshaft bushing is a regular wear item, located inside the transmission tailshaft housing. It should be replaced when replacing the tailshaft seal or when a driveshaft failure has occurred. A worn bushing will cause excessive side-to-side movement of the slip yoke and create a vibration or leak. Replacement bushing and seal fits GM Powerglide, Turbo 350, Saginaw, Muncie, Bert and Brinn transmissions.