I am a certified Yakima Installer, so here is what you are supposed to use:
Railgrab 4 Pack System
-This is what connects the Yakima crossbars to your raised side rails
58" Crossbar Pair
-These are the crossbars from Yakima that all Yakima roof mounted accessories can mount to directly including the LoadWarrior
LoadWarrior
-This is the load bearing piece. It can mount directly to round, square, and factory crossbars on the 06 4Runner.
I recommend a direct mount for now, and in the future considering a Yakima crossbar system. The Railgrabs are easily removable within 5 min, and can be shifted on the factory siderails however you want. All Yakima Round bar accessories are compatible and the entire system can be transferred to a new vehicle if you ever trade for a newer 4Runner (not likely I'm guessing).
I've had my Railgrabs for 3 months so far with wind fairing and have not noticed any mpg drop, warping, or load issues.
Here is a link to
Yakima's Fit My Car
Happy Trails!
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