As Steve mentioned check your trailer ball height while the trailer in sitting on a flat surface and parallel to that surface. Find a flat surface and measure the front and rear of the frame to ground and then measure the ball height.
The important thing is you want the trailer to ride parallel to the ground because the Airstream suspension can not correct for not riding this way because of the type of axle used.
If you are using a weight distributing hitch the hitch will most likely bring the ball back up to that height once the hitch is loaded.
Just make sure the front fender of the TV does not raise when hitched. If it does you will have to reset the angle of the hitch rearward to correct this.
If you head and ball are in good shape I would look on E Bay for a used shank before dropping the $200.00
WBCCI 12156 AIR 3144 WACHUNG TAC NJ6
2004 Excursion 4x4
1991 34 ft. Excella +220,000 miles, new laminated flooring, new upholstery, new 3200 lbs axles