The Nissan Path

I been having a problem with my 1997 Nissan Pathfinder SE in which since day 1 I notice that the steering is way off, when I am in low speeds I keep the steering wheel center no problem, as I increase speeds (highway) I have to tilt the steering wheel usually to the right to keep it aligned and at time to the left. When I went under my car I notice that the bushings of sway bar end link were broken in which I bought new sway bar end links (haven't installed them yet). When I go into bump I hear a knocking sound from the front wheels in which my mechanic told me that I also need new Axels in which I am currently in the market looking for new axels. Any recommendations?

You can get new, Cardone Select axle shafts with a lifetime warranty from Rockauto.com for $56 each+shipping.

I would also have a look at the driver wheel well and shock tower for any excessive rust or possibly rupture of the metal around the shock tower. There has been a recall for this and the symptoms that you are saying could fit the issue...

you can also remove the air box and verify if the steering column shaft is hitting the shock tower... this would mean it is broken (the shock tower).