Steering box keeps loosening up

[AussieinNC]

Sounds like the steering box mounting points are flexing when steering loads are placed on the chassis.

I have cured this issue by drilling out the mounting holes both sides of the chassis and installing solid tube stock and welding in to strengthen entire mounting face. I box in the frame to add strength.

The mounting bolts then compress against the tubes, taking chassis distortion out of the equation.

Make absolutely sure the chassis is not cracked from the flexing...if it is, weld it up and place reinforcing plated across the area and fully weld.