On my 3rd gen Dodge, 05, I discovered that the rear of the bed to rail height was a little more then the front or the bed to rail height. I believe it was about 1/2 to 3/4" difference. Don't ask me why. I discovered that difference when I first purchased my 05 and I loaded my then, Lance camper in the bed. The camper was going to come down on the rail at the rear of the bed. I had the the factory bedliner in the bed and I had to add a full size thick rubber mat to gain a little extra heigh. The advantage to all this is that, with the bedliner screwed to the bed and with the rubber mat in place, the camper would never slide. I also had the HappiJac tiedowns. My 2nd gen Dodge, 95, was the same depth, front and rear.