Yup, ever since the firestone/explorer fiasco years ago, some companies just went nutso.. Most say they will only do stock size on explorers. Others, stock size in general..
If you bring them in loose, you can usually get away with telling them its a ranger, or even a jeep and then they won't care.
You know its just following "policy" since they will have no issues if its a navajo or mountineer which is the exact same as an explorer..
~Mark