The axles are barely suitable for a fully loaded trailer, provide they are loaded equally. Typically the two axles do not carry the same load. You could easily overload one axle.
Personally, I'd rather have 5000# axles so you have some reserve capacity. Better check your tire ratings and capacity to be sure you are not close to overloading them.
Trailer delivery folks are really bad about setting their brake controller as high as possible and let the trailer do ALL of the braking and saving their truck brakes.
Ken