Power steering problems

The problem started after offroading today. When I am at a stop I am unable to turn my steering wheel but as soon as I start moving the wheel moves easily. Went to the self car wash and cleaned it up, the car cooled down and I started it back up, the wheel turned fine. Started my 3 hr drive home and and once the engine warmed up again it became hard to turn the wheel at a stop. Anyone have any ideas? I'm no mechanic and need some help.

 

Bump for help!

 

Is the pump whining? I'm not sure if there is a PS cooler on these, but it maybe clogged up with mud causing an overheat? My pile is down right now because of a bad PS pump. 2nd time...

 

Perhaps the belt is slipping?

 

Yea the pump whines everytime I try to turn it at a stop or slow speed. My truck is still under warranty so I am going to try and take it to Toyota on my next day off. Just sucks real bad parking right now

 

Sounds like a PS pressure issue. Slipping belt may not let the pump function properly. When you accelerate pump speeds up a bit. Belt first, check fluid and for leaks/bad pump second.