Suspension / Steering issue

[Mustang1989]

A few weeks ago my '05 F250 developed a steering problem. About 5 times out of 10 when I turn a corner, left or right doesn't mater, my steering wheel does not correct itself back to center. Like I say it started a few weeks ago, and today I almost hit an oncoming car while turning. I also noticed a mild "Clunk" or "Pop" sound coming from the front suspension somewhere. It'll happen every couple of minutes while driving, or when I come to a complete stop at a stoplight. I've made an appointment to bring it in, but in the meantime does anyone have any suggestions for me?

Thanks

[CHTOOL]

my 2002 f350 just started doing the same thing, please let me know what the say. thanks

[Mustang1989]

I brought my truck to the dealership a couple of weeks ago. The shop manager told me I need new upper and lower ball joints. They want $1400 for the job. I refused at the time. I don't know much about steering or suspension, but I'm not so sure ball joints are my problem.

Yesterday I made a normal right turn after a stop sign, but this time my steering wheel almost locked right. It took both hands to pry the wheel back to center, and I had to fight to keep the wheel from going right for about a block. Could it be my power steering pump, or is this a sign of bad ball joints?