Questions for those that have alleviated or reduced the diff howl

I know that a few people have had some minor success in drastically reducing the howl or even eliminating it.

How bad was your howl before (1-10)?
What specifically did you do?
How bad is it now(1-10)?
1 being "meh I can sort of hear something"
10 being "WHAAAAT? I can't hear my radio over this F*cking 400hz tone even at 50+ volume on my radio")

Bonus question: Anyone have the howl before and then eliminate it with a re-gear?

I'm hoping we can see some patterns/similarities. I go through waves of being able to tolerate it to finding it completely unbearable. Tonight, it I noticed a faint howl at ~30mph. So its grown from 55-57 initially to 45-68mph and now it looks like the 30 mph range wants to play.

 

I believe there's a few people here with 2 inch lifts that have decreased the howling noise.

 

I guess it's too few to keep this thread moving