An 8000 loaded trailer will have +/- 1000 lb tongue weight (always figure 13 percent ratio of trailer gvwr). What is the gvwr of your Yukon? How much weight will you be loading into the Yukon? Passengers, gear, dog, options, hitch, etc. When you add all together, you will more than likely overloading the Yukon. Manufacturers Tow capacities are deceiving. You run out of payload long before you reach max trailer weight the tow vehicle is rated to tow.
P rated tires on the Yukon are soft and not a good fit for towing heavy trailers.
If you want an 8000 lb trailer, I would get a larger tow vehicle. The max I would want to tow is 6000 lb trailer loaded.
You will get a lot of opinions, but if you exceed any ratings including payload, your trailer is too heavy. BTW ignore what dealers say, they don't care about your safety.
