Hi, I apologize in advance for my English.
I recently bought a used discovery 5 with 80k. Now I observe vibrations and booming noise from 115 km/h. The wheels are balanced. I tried to put the transmission in neutral and the noise with the vibrations does not change. Discovery got a new engine in 40k. I had the same problem on my RRS 2014 and no one was able to solve it (also a new engine).
Some ideas?

 

Had this problem with my Disco 2 after the front drive shaft was replaced. Though I can't definitively say that was the issue as I just stopped driving it on the highway before junking it.

Tires had been balanced but were probably not matching and/or different age/condition

 

Very hard to diagnose a vibration like that on a forum. Any codes if you connect a code reader?

Would take it to a good Indy mechanic and have them look. should be an easy diagnostic in person.