This is THE solution for your 2004 – 2007 QX56 with the unusable factory rack sytem.
The 430/TK system has a quick release feature to remove the bars in a matter a minutes once unlocked. Using this system between the factory racks allows for a narrow enough bar spread that any Thule or Yakima box will attach. This vehicle has the Thule 688BXT Atlantis 2100 in Gloss Black which provides maximum cargo capacity with great looks and aerodynamics. Any Thule Ski, bike, or boat accessories can also be mounted easily to this crossbar.
Another great solution from your local Rack Attack. Stay tuned for more fun setups.