I took the column and steering box out of the truck and discovered the roller was seized on the sector shaft. I had a NOS sector shaft that I put in after a complete rebuild of the steering box. It steers great now. Apparently the roller was "skidding" along the steering worm gear instead of rolling. Luckily the worm gear was in great shape. Down the road we'll probably install a new roller but for now, we're set. Thanks to all for the help.
