Set up is 2009 f250 , crew cab, 4x4 , v-10, 8500lb loaded TT, 1200lb tongue weight and 4 point equalizer. Trucks squares 1" in rear when hooked up. Squats 2+" when I load the golf cart in the bed at the same time. Want to level out the sag. What is best solution. Truck used 95% for towing.