Have to say this is my one real gripe with my new to me 2013. After having a 2003 and always filling with the trucker pump at full bore, I'm still having issues getting the little pump to open both flaps enough to not pop off and stop filling quite often. I tried filling with a trucker pump once on the maiden voyage home from Texas where I purchased it, and holy mother of a mess, I paid 2 or 3 bucks for diesel that I'm pretty confident went all on the ground. Would not even start to take it even when squeezing the handle as little and gently as possible. Miss my old girl every time I fill up, lol. Not thrilled with the open to the elements flap either, especially being up north with our lovely winter roads and dirt roads. The lid does not seal enough to keep all that dirt and water out of there. Ordered the o-ringed cap from Geno's. Unfortunately noticed the green plastic ring around the top outside flap is cracked at the bottom edge, so not sure how effective the cap will be. Have to look into replacing that, but pretty sure will Crack again seeing as how that is where the weight of the pump nozzle rests if you let go of it. Oh well, still a huge upgrade in truck compared to the '03.