I recently purchased an 03 WRX 4D. It has a light weight flywheel, stage 1 clutch, and a short throw. When I bought the car I noticed that the clutch was not consistent with the feel. The car also does a mild grind going into first sometimes as well as 4th. I bled the master cylinder, and after hours of frustration I was finally able to get the pedal to return all the way back and have good feel. I thought this would fix the grinding and pedal feel but it is back to square one. If I am driving on the freeway staying in 5th for a couple hours, the clutch does not return all the way up. I have to pump it several times for it to fully return. I am not sure if the slave or master cylinder is leaking or broken, or if there is some totally different issue. Is the mild grinding from the clutch issue or is it possibly the synchros. The guy who had it before me was also using synthetic transmission fluid. I have heard this can be horrible for transmissions.
Any input would really help. I have asked shops and auto part stores and I cant seem to get a good answer from anyone.