The transmission oil was changed a little over a month ago by my mechanic with GL5 spec gear fluid designed for Borg Warner super t-10's and per the Chilton's manual I have for the car. The same mechanic adjusted the free-play on the clutch as well as it had none when I purchased the car and the pedal was very difficult to push in, now its in the 1-1.5 inch range and the pedal is easier to use. The bad thing is this car sat for 16 years in a garage until I bought it last September and I'm just gradually getting it work again in my garage. This issue isn't new which prompted me to take it to my mechanic to complete the fluid change and the adjustments. However, a little over a month later I'm having the same problem again.
I have noticed that sometimes if I hold the clutch in with the car in gear when at a stop light, there is sometimes a vibration/noise that occurs very briefly then goes away. Generally, I've been leaving the car in neutral at stop lights though sometimes I do leave it in gear anyway.
Thanks again for the help and your time.