All throughout the manual transmission components, you will find a variety of bushings and bearings. These are located in the front input shaft or the rear output shaft, as well as in the shift shaft and drive gear. They help with part rotation and movement, turning and engaging the vehicle transmission.
If the bearings in any of the vehicle transmission components have wear and tear, you might hear something before you see it. You may hear chattering or squealing, but you may also feel vibrations and shuddering when accelerating or shifting gears. Replacing these parts as soon as it's noticed will prevent serious transmission failure.