I spoke with the folks over in Austin about this before. In Texas you register your Gross Vehicle Weight, which is the curb weight of the truck plus it's load. Most trucks just get registered using the GVWR since it'll come in below 10k. However once over 10k you'll change classes.
The registered weight doesn't necessarily have to match the vehicle's GVWR. If you have a 14k truck then you can have it initially register at 10k, but you will then be restricted to this weight. I was told while it is possible, "It's ultimately up to the Tax Assessor to accept or decline the proposed weight classification. The Tax Assessor has the final say on the vehicle's classification."
I asked what would happen if you got caught over your registered weight and I was told that you would have to pay for the additional weight before you can continue operating on public roads. You may also be issued a registration violation citation depending on the situation.
Now the difference between "is it legal" and reality can be pretty far. Since 10k-14k F350s all appear the same from the outside, chances are you aren't going to have an officer pulling you over because of weight. Overweight tickets for us RVers are pretty rare anyway, but still possible. If you want to stay completely legal then have the dealer correct it. Instead of costing you $54 a year, it would cost you $110 a year to be at 14k.
Thanks for the reply, that is what I found also. I will stay as is but when renewal time comes I will go to 14k license for peace of mind.