Those ratings don't have much to do with "legal" unless the place where you are licensing the vehicles collects taxes on the basis of weight, in which case you might get a license violation for carrying more than you paid to carry.
Triker33 said "if it has registration plates on it." That varies also, since Oklahoma does not require registration of trailers for private use. I suspect New York, however, wants you to register it and pay an annual fee or tax. In that case, if the tax is based on registered weight, then it is not legal in New York to exceed that weight.
