I think TJ touched on a possible solution in her previous comment. You may want to look into replacing the springs in the lower part of the wiper arm. Also, make sure the lower wiper arm is pushed fully down on the pivot post. These are the only things I can think of that would cause this problem with different wiper arms.

well i found the problem, after taking it apart again i noticed while pulling the arm there was slop in the pivot shaft! so thanx for the reply's. hopefully i can replace them without to much trouble.

no it calls for 18 inch and that is what i put on and even tryed another set of blades and not the cheap ones i bought the new rain ex after the anco didnt work very well thinking the blades were old but didnt help at all.

Did you just replace the same size that was on your truck or did you look it up for the correct length? Sometimes you use only whats available and it is smaller than what is supposed to be on the vehicle.