Synchromesh gearbox is similar to the constant mesh gearbox in which dog clutches in the constant mesh gearbox are replaced by synchromesh devices for smoother engagement of gears the gears on the main shaft are free to rotate wrt the main shaft whereas the gears on the layshaft are fixed ie there is no relative motion between them. The latest version of the constant mesh model is the synchromesh gearbox this is a manually operated transmission in which transmission changes occur between rotating gears at the same speed the gears can roll freely or they can be locked on the layout shaft in this sort of gearbox synchromesh is an upgrade on the dog embrace really. Synchromesh gearbox or transmission system is a type of transmission system in which the dog clutches from the constant mesh gearbox is replaced with the special shifting devices known as synchromesh devices which makes the system compact and also provide smooth and noise free shifting of gears. Synchromesh gearbox working principle description of synchromesh gearbox working principle jun 05 2020 by horatio alger jr last version synchromesh gearbox working principle synchromesh gearbox is similar to the constant mesh gearbox in which dog clutches in the constant working of synchromesh