Loud and rough in 4th and 5th gear

Hey all, I got an interesting issue with my 1st gen.

So I replaced my manual transmission mount a couple of weeks ago with a 4x innovations mount and I read that there will be more vibration in the cab with that mount but since then it's been very loud in the cab, almost unbearable. I did have a PO451 code with a rough idle but I got that fixed with a new purge valve and it helped. I also noticed that once I shift into 4th it feels like the truck is running very rough (more pronounced than lower gears), it's like a vibration and a struggle bus to keep power because once the gas pedal is left off it engine breaks pretty quick. Overall I'm just curious if its just because the truck is older (04 v6 4x4) with 225k on the OD well maintained or if something went wrong. any help or opinion is welcome. thanks

 

something went wrong IMO

Does your shifter stick shake noticeable at any speed in 5th G

 

I have not noticed anything I will check tomorrow

 

No shake in 5th gear, just vibration.