The tail door has been cracked at the edges of the window since I picked up the truck. A few weeks ago I noticed the crack spreading so I drilled a hole in the end of the crack on each side of the door to stop it from spreading. Tonight I went out and layed down a weld along the crack to seal it up and ground the extra down. Viola. Tail door is much stiffer and uniform when I close it now. What a difference a little thing like that makes. I know this was covered before but just my 2 cents.