I carry either a 16ft. canoe or a 17 ft. kayak on top of my truck sticking out forward over the hood. Since I have a front receiver, I have made a "T" shaped support that comes up in front of the bumper and holds the front of the canoe. I tie it down with ratchet straps. I use a Yakama bar with canoe clips on the roof of the truck. I have had no problems at highway speeds and in cross winds. The key is good tie down straps and solid support.