I have a 04 GMC Sierra 4wd with a 6 inch suspension lift, I've been to two aligment centers and neither could properly align the front end. The part out of alignment is the caster on both sides. My truck pulls to the left, the toe is in the green and the camber is in the yellow on the alignment print out. Any suggestions on what the problem could be?

Thanks!  

If you could tell me the readings in degrees for both caster, camber  

The caster was, driver's side 0.8 and passenger side 2.0, I know they are supposed to be within a 1/2 degree of each other. I can't remember the camber readings but they were in the yellow on the Hunter alignment rack and the toe was good also. Is the truck supposed to be adjusted to GM's alignment specs or should Rough Country have different specs for me because of the lift? Thank you for your help!!

John  

It should still be adjusted to factory specs.left caster should be 4.25 and right caster 4.50 degree + or - 1.00 degree
for some reason your lower ball joints are to far to the rear

1.Has it been right before or is this a problem just since the lift was installed?

2.Have you been wheeling it or hit a chug hole?

3.Look real carful to see if anything is bent.  

Yes it was fine before I installed the lift, I only drive it on the street and I'm very careful how I drive, I baby the truck! Nothing appears to be bent. I'll try one more alignment center and see what happens! Thanks for your help!!  

Almost sounds like a defect in the lift kit causing it not to align.  

Yes, you are absolutely right! After a year of trying to get some response from Rough Country, one of their techs told me about a problem with their non-drop torsion bar system and sent me a new set up to drop the bars and eliminate all the other garbage causing the problem. Although I haven't been to an alignment center since the modification, I can see why it would cause the problem. I'll write you again after the alignment. Thanks again for your help!!  

Cool, glad you got it figured out! Let us know what the alignment says!