i have a 89 mustang gt, when ever i shift i hear a noise and it sounds like the tranny is jumping, if i really give it gas in first gear it gets really loud, it does it with the clutch pressed in. could it be a mount or bearings?

 

With the clutch pressed in the transmission should not be turning so that pretty much rules out any of your theories.

 

does it sound like it could be the universal joints? thank you