Crooked tow hitch?

My 2001 came with the factory tow package. The other day, I was at the end of my driveway looking at the rear of my XJ, and noticed the tow hitch hangs a little low on the drivers side. About .5" after I measured it. All the bolts for the hitch are tight. My bumper is on straight. Could my frame be tweaked, or could this just be a manufacturing variation? If my frame is suspect, what else could I look for to confirm?

First measure the brackets on the hitch and make sure they are the same height, if they are the same length then move on. If your bumper attaches like my 88 XJ then there are slots in the bracket to allow you to make the bumper level. You may have bumper sag, not a bent/drooping hitch.

The last restort is to take it to a body shop and pay them to put it on the frame machine and have them check it out. You may have to pay for an hour to two of labor, but for $50 to $200 you may find out what going on.

I think my bumper is ok, because the gap between the bumper and rear hatch is constant across its width.

Anyone else have this problem?