The car might be pulling to one side because of a misalignment.

A lot of times a person doesn't need an alignment unless the ball
joints go bad or get replaced............or if something else has moved.

When I do ball joint tests, I actually pop them loose, and show the person the difference between a good joint and a bad joint. Some places do the shake 'em and sell 'em test, which I believe to be inadequate.

When I replace balljoints, I also can check the alignment using the portable alignment set like they use in the garages at the Indy 500.

If you want a quick check of the alignment, get back with me.-Bob

This may sound like a dumb question.......When you replaced the axle,
how much transmission oil did you have to add to bring it up to full?