2006 Explorer 4.6 v8 has no power to tow up mountains?

I used to tow my 26' boat with a 06 Explorer Ltd 4.6l and that 3 valve engine is a strong engine (same engine in the Mustang GT then) but as others say it loves to rev to make power. When I would take inclines towing that boat the 6sp trans would downshift and the engine would really sing but I must admit I liked that V8 sound.
I never had it in the mountains but it never let me down towing.