Two days ago I started having difficulty turning the steering wheel in my Nissan Altima. It would turn ok at first but about half way through the turn I would have to force it to move, and then it would not return by itself -- I would have to physically turn it back. Same thing with turning in both directions. This happened all of a sudden, but after it started it didn't get any better. Checked the fluid-- it was fine. Just had the car checked and its oil changed, and they didn't mention anything out of the ordinary except that I'd need new break pads in a few months. I have been hearing some creaking when turning the car but thought it might just be from the cold weather. Was worried the steering problem might be the U-joint. We took it to the car wash because my fiance had a suspician it might just be road salt build-up. Washed the undercarriage area-- now the car seems to be turning normally. Is this something I should continue to worry about, or does it sound like there was just road salt/dirt build up?