Check that hitch on the Yukon.
If the factory installed hitch is made of thinwall round tubing from the passenger side to the drivers side, then it might be a weak link. Check it carefully for cracks, and after each tow. Check the paint at the round tubing to square tubing welds, if they start to crack away the paint, or the welds show signs of rust or cracks there, stop towing, and get another vehicle to return your trailer to storage.
A good way to check for stress on the hitch is measure the square part to a fixed point on the Yukon. Then hitch up, and lift the trailer jack. If you see any significant bend in the square tubing to round tubing, you have a problem.
Fred.
