Need some help

I have a 1990 Maxima SE. While driving, after I make a right turn, when the car is going straight, the steering wheel leans to the right. The same happens after I make a left turn, the steering wheel leans to the left and the car will be going straight. I've had the car aligned and it still happens. The left front wheel experiences uneven wear. Also, after 85+ mph, the steering wheel bobs left to right.Also there is a creaking sound when I turn the wheel in either direction when the car is stopped(ex. while trying to get out of a parking spot). Any suggestions on what it could be or any parts I should replace? Anyone else experience similar problem? Any input would be appreciated.

I am not sure but it sounds like the circle plate that spins between the strut, and the spring plate. Or you have bad lower control arm bushings.

I replaced the bushings about a year ago. Could it be the rack and pinion? I'll have my mechanic check it out. Any other suggestions?

PS- Is it possible to check yourself if those parts need to be replaced and how?