Well the issue is serious and not that easy...i won't suggest you to aaply ur own mechanical experties to it since mechanical issues in any kind of vehicle are very sensistive its a better idea to get the mechanice to ur car
and the thing is what i see is that the problem lies in the gear box since the bush present in ur box have lost their energy and u wud need to get them replaced 
for more info plz contact
neatautos@hotmail.com
Reagards
Walleed
Neat Autos