Steering the vehicle, gradually became harder (it would pull slightly to the right. when checking air pressure, i noticed the front tires were worn excessively. i then took the vehicle in for repair, where i was told i must have hit a curve or had been involved in an accident, neither was the case. i had to have the complete front-end of the vehicle replaced by auto nation south bay nissan of hawthorne,ca invoice #685460, which included: rack and pinion, steering angle sensor, gear and linkage, switch assembly combination, and core.