Hey guys, I bought a ‘16 Yukon XL Denali and found out about this issue after I started getting headaches and pressure build up in my ears (I am an audiophile). Thankfully I was able to completely solve this issue.
I have Wrangler duratecs on on my mine 275/65r18 and they are pretty noisy off road tires. I’m completely satisfied with my Yukon xl and it rides like a luxury ride should. My fix was #1 swapping out the mag ride struts / shocks with the base model (mine were leaking and rock hard) non-air ride ones front and back #2 added the roof rails to position 1 and 2 (closest to the front of the car). I suspect adding two more roof rails to the back should add even more structural strength to the roof.
secondskins had a 25% sale on damplifier pro (better than dynamat) and MLV so I bought that before (not needed now) but I’ll still put it on.
hope this helps someone out in the future!