After I drive a bit the clutch seems to drop about 1/2 inch. Otherwise it works fine though. Is this the master cylinder or the slave cylinder or both?

Since the car is getting older I was considering replacing the clutch and brake cycllinger and also all 4 calipers. Is this just a was of money or a good safety precaution?

 

Have you checked for any fluid leaks at any of the fittings or hoses? Have you checked for any leaks on the inside of your car where the clutch pedal is connected to the "linkage rod"? Determine what it is first.

 

clutch master cylinders are known to go out. mine did.