Leaking Transmission Oil

[tmho]

My car is a 1992 Sentra Classic with automatic transmission. It just ran 120,000 km. About 1 year ago, it started to have some strange noise occassionally. It seems like the noise (when driving a manual transmission) when you shift to a higher gear to soon. I bought it to the repair shop and they could not fix it. About 2 months ago, I bought it to the repair shop again trying to fix it. They said the ignition time was incorrect that caused the noise. After adjusting the timing, that noise seemed getting lower and less on the first day. After a few days, it is just the same. About 1 month ago, I found transmission oil leaks. About 1 drop per day. I bought it to the repair shop again to fix the leak. They replaced the seal at which the driving shaft is connected to. But it was still leaking. Then they replaced the driving shaft but the oil is still leaking from that area. The mechanic said it is the problem of the gear box and I have to replace the gear box (whole transmission) to stop the leak. Is this correct? Should I trust that repair shop? About 1 week ago, I found another noise coming out intermittenly. It is something like the noise coming from grinding metal. Are those two noises coming from the transmission and indicate something wrong that need replacement? Since a new transmission is very expensive, the repair shop suggests me to replace it with a rebuilt transmission which cost less. Is this a good suggestion.

[elwesso]

Have you checked your trans level at all??

could you describe the noise? Does it correspond or change with vehicle speed or does it do it all the time.....

[tmho]

Have you checked your trans level at all??

could you describe the noise? Does it correspond or change with vehicle speed or does it do it all the time.....

Thank you for your reply.The transmission oil level is okay. I mean not lower than normal.The first type of noise is like the noise you will hear when you shift to a higher gear too soon in a manual transmission. Most of the time it happens during acceleration. It usually happens between 10km/h to 40km/h. It only happens about one third of the time when the speed is between those speeds. The second type of noise started just about 1 week. It is just like the noise you can hear in grinding metal such as regrinding of brake disc and brake drum. It usually happens between 20km/h to 50km/h. At the beginning, it only happened 10% of the time. Now is about 20% of the time.