I used a 2005 z-71 tahoe luggage rack on my 2008 Denali. Bolted right up. They are beefier than the stock rack. However, I did end up using 2x4 lumber to span the rails and mount the tent. 2 reasons: first, there is NO room for man hands under the stock rails to tighten the mounts. Second, the cross bars flex and seemed Iike it would rub the roof when people were in the tent. I bought a FREE SPIRT RECREATION tent and have been happy with it. It sticks up higher because of the 2x4s, but a homemade air deflector solved that.
I measured my 2017 Denali and it has a wider roof line, so that rack won't work unfortunately. However, if you the kept stock setup, used spacer boards on top of the bars, and let the load rest on the rails, it would probably work. Just make sure to have the load points near where the rails mount so it's above a structural area-ish
Or, buy the rack mentioned above and be all set. Unfortunately there's not much aftermarket available for these trucks and that type of use.
I measured my 2017 Denali and it has a wider roof line, so that rack won't work unfortunately. However, if you the kept stock setup, used spacer boards on top of the bars, and let the load rest on the rails, it would probably work. Just make sure to have the load points near where the rails mount so it's above a structural area-ish
Or, buy the rack mentioned above and be all set. Unfortunately there's not much aftermarket available for these trucks and that type of use.