I had a car that had a really bad synchro in third gear and i mean REALLY BAD!! I started looking for a easy fix thinking there wasn't one. I came across a forum with a solution. Put the car in neutral and move the shifter with the clutch out torwards the gear that grinds. It should not grind! If it grinds your pushing it to far!! You should feel a slight resistance, once you got it there rev the engine up to 3000 rpm for about 10 seconds. they recommended 15 but you can do it again if you notice a improvement. Take it out and it should be fixed. What they were saying was after a car sits for awhile something builds up on the synchro and this removes it. I'm not a trans tech but it worked for my car! (A 95 Mustang at the time. I know I know) I do want to say this probably isn't the best thing for a transmission but it did fix mine. I would also recommend replacing the fluid after you do this! When I was reading the forum a lot of people had tried this and it worked for a lot of people. It didn't work for everyone, but mine was so bad i couldn't see making it anyworse so I gave it a try and it worked!!! I couldn't believe it did. I sold the car shortly after so I dont know if it's a permenant fix! I take no responsibility if you do blow up the transmission I'm just throwing this out here because I would have liked to known about this earlier. If you do this post your findings so anybody else thinking about trying it will have more than one persons results with it.