I'm using the FedEx extension for shipping methods/rates. However, when the cart exceeds 4 items, the shipping method options are empty. There is no {error:shipping_method} displayed when this occurs. Are there limits on the number of items or weight that the FedEx extension will calculate? Or do these limitations possibly exist in the FedEx API?
In the FedEx Rate API docs there is an error described as "660: Weight exceeds limit allowed" which leads me to believe that this may be caused by limitations within the API itself.