My preference is a Dodge Ram 3500 (1Ton) with the Cummins 5.9 ('05-'06) 3:72 gears. My '05 Ram is rated to tow over 14,000 lbs.
Maybe you know this, but. If you have a trailer that has a GVW of 10,000 lbs or more in CA you'll need a class A license to pull it whether it's loaded or not.