91 Suburban Steering Box

I just put a new(remanufactured) steering gear box in my 91 Suburban. It seems kinda tight. It doesnt like to return to center after a turn. I know that there is an adjustment screw on the top of the box but if I adjust that it voids my warranty. Do any of you know if it will loosen up after a little while or what? Could my power steering pump be weak?

Thanks

Sounds like the gear box is over adjusted to remove center play, talk to your supplier about this.