Review on EXEDY MC229 Clutch Master Cylinder: Reliable Performance and Smooth Shifting by Jontrell Fernandes

Clutch problem (couldn't always shift). The Mazda dealer said the leak was in the slave cylinder area. I ignored the online advice to replace both the slave and master cylinders. Exchanged slave, problem remained. If the master were replaced, the problem would be solved. These parts are cheap and replacing one instead of both doesn't cost much more. Bleeding the clutch line is probably the most time-consuming aspect of a repair. It's better/cheaper to replace both cylinders, make sure you're done, and then bleed.