i have a 86 gxl and my i believe my transmission is finally quitting on me. Almost every time is shift it shifts hard and will buck my transmission and i can here a loud click/thud coming from my drive shaft/rear end. i installed a short shifter so my whole assembly is exposed so i can see all of this and hear it very clearly as i drive. Does anybody have any idea of what exactly this could be? I thought it was just my driving because i did learn stick on my car but i can drive other Manuel transmission cars very smoothly so i ruled that out.

 

Sounds like your front diff mount has broken, Is very common