taz101,

Although not real familiar with a '58, here are a few thoughts.

On my '51 AD with straight axle, I installed a Saginaw box out of a '76 Nova. This was a police car and the box was a COPO (?) quick ratio unit.

The truck handled very well at all speeds on most roads.

Did your basic steering geometry stay the same. The pitman arm and steering arm should be in almost the same plane.

Could it be a alignment issue. Are there other front end components that could be worn.


Stuart