Is that trailer weight the Montana 3150? If so, it has as Gross Vehicle Weight Rating of 13,965 lbs. The 11,000 is an unladen weight -- not useful in judging towabilty.
Your 250 has a tow rating of 12,500 lbs. We like to knock 10% off that to allow for passengers beyond the driver and truck cargo including the hitch gear. That moves the maximum trailer GVWR that you should tow down to 11,250 lbs Moreover the 3215 has a pin weight of 1965 lbs. That may be a bit heavy for the rear axle rating of a F250.
All in all, I would say, lighter trailer or beefier truck.