Ah and I return once again to the forums because Big Mamoo (that's her name) is having issues!
I took my 6.9 out to the desert to go shooting the other day, and when I parked on my slanted driveway backwards to unload various things, everything seemed ok.
The next morning when I came out diesel fuel was pissing out of the bottom at a steady stream, on climbing under to see where it was leaking from it looked as if it was coming from the left side, running along the frame where it eventually came out the bottom. I assumed the fuel lines were bad. Upon closer tinkering and inspection the lines seem intact. The wet spot is only coming from the frame to where the front of the tank is and running down halfway to where it is dripping. I ran the truck on level ground and could find no leak. I also noticed what I assumed to be the breather tube which comes out of the top of the tank was wet, so is it possible that somehow I created a vacuum, and when switching to the rear tank and parking it on a slanted driveway backwards that somehow I broke the vacuum and created a siphon effect which pissed most of the diesel out of the rear tank? I am really confused on this one. Thanks,
-Linny

 

I found the tanks spilt at the seam and will fill with dirt and aren't noticeable but on certain angles