I have a truxedo soft tonneau cover and was wondering if anyone has solved the problem of air getting under it causing it to flap. I have bed rail caps so I assume the air is getting under it from the front. I tried a piece of rubber under the entire front of the frame hoping that would seal it up but it didnt work. Any ideas?

 

The flapping is simply caused by a pressure difference on top and under the cover. The air is going over it, causing a low pressure spot on top, and there is no movement underneath. Because of the low pressure pocket on top, the tonneau wants to lift off, but obviously cant so it falls back down and repeats process. The only way to fix it is either tighten the tonneau if you can adjust it. Otherwise, you're outta luck unless you get something more rigid