05 monte tranny knocking

I have a 2005 monte ss supercharged and the tranny is doing some serious banging and knocking..flywheel is tight..no metal shavings in fluid or around tranny..the noise goes away then I rev the engine or driving..but if I floor it it makes a grinding sound at high rpm..any ideas? thanks

probably should take it to have diagnosed, are you sure it is the trans?

Check the date.....