Well, all, I looked at it further this morning before coming into work.
The tractor is 3 months old, so all tires should be be new.
Before doing anything, The bucket was 2 inches higher on the right than the left. Measuring from the floor to the grease nipples on the loader arms indicated that the right side of the loader arms were higher than the left side from many nipple locations.
I then checked the tire pressures. The left rear tire was low, so I put air in that tire to match the right tire. This doesn't seem like it would make any difference for this problem. The front tires were identical in tire pressure.
I took the bucket off, and the quick attach points on the loader arms were still offset by 2 inches. So the bucket is straight. The heaviest thing I've lifted is buckets of dry clay. It's a HD bucket with a tooth bar.
When the salesman arrived with the brand new tractor on day one, we took the loader arms off the tractor and put them back on. We had some problems since we weren't on level ground. So I took the loader arms off this morning. With the loader arms off, the mounts hubs for the loader are the same height. I put the arms back on, and now the bucket is 1 1/8 inch higher on the right then the left, which is much better than the 2 inches.
It also looks like the left hydraulic cylinder and right hydraulic cylinder are not extended the same amount. I think there is about 1/2 inch of difference (if I remember correctly). I may be the real problem.
I'll check to make sure the mounts are tight on the tractor. I'll take another look tonight, or tomorrow morning. If it's still off, I'll contact my dealer.