I have had the same 17.5 boat and trailer for quite a few years. Have towed it with two different vehicles. Have always been amazed at how well items in the boat travel. Everything pretty much stays where it is even on very long trips. This past spring my buddy bought a new truck so he insisted he drive. when we got to our destination everthing had shimmied ahead in the boat including the battery which was strapped down in a case. Pliers, poles, tackle etc. I also noticed some fasteners had come loose on tail lights and also the ones holding the engine on. I monitor this stuff frequently and this has never happneed before. Is this related to a height issue on the hitch or stiff suspension? Any ideas? I think next time I will just drive my truck. Not worth the risk of something shaking loose.