Since we know the cover is to be down before closing the tailgate and the seals around the bed are critical to prevent water intrusion, we are probably pressurizing the compartment as we close the tailgate. It does seem easier if I gently put it almost closed and then quickly open an inch or so and push it closed. I think this reduces the volume of air I am trapping.
When we first got the SSR I too couldn't figure it out, but my husband showed me that if you press down on each corner til it latches you don't have to slam it..... It has also gotten easier now I can shut it from the center without going to each side and I still don't have to slam it. Try that before you go to the dealer, especially one who has had little or no time to acess the SSR.
I never slam my tailgate. After I close the tonu, I gently press the tailgate close until it clicks solidly. If I use too much pressure or slam the tailgate, the tonu pops open on one side partially. I am extremely pleased with the seals in the cargo area.
I am sure most of you, with your wifes, have had troubles with the tail gate being to heavy. I have just redesigned the procedure to include more bulk shock cord from the netbar to the tail gate. This will allow you/wife to lower/raise the tail gate with very little effort! :flag