dull thump thump or clunk noise heard on 1999 Ford Mustang

i hear a dull thump thump or almost a clunk or low tone pop noise while shifting through the kinda reminds me of the sound of a bad engine the engine is slightly lifting as the torque is applied through acceleration,then when clutch pedals depressed the torques gone and lets motor drop back kinda feels like it may be inside trans though.could something in clutch assembly make this noise.

Asked by for the 1999 Ford Mustang