I say too much. I would be the tongue weight is over the recommended tongue weight for the flex, which is 516lbs dry. That is probably 650lbs ready to camp. Also, the UVW is probably not what it comes out ready to camp, but looking online, it is fairly close. Fully loaded, I bet you are closer to 4800lbs ready to camp. Plus, all the people and the tongue weight, you will probably be overloading the GVW of the Flex. Also being Front Wheel Drive, You would need a read good WDH to keep the front wheels on the ground. Even me, being a little daring, probably wouldn't do it.
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