Power Steering?

I have a 2015 KW T680 with the Cummins ISX in it and I'm having trouble with the power steering for a while now. Lately it had been getting harder and harder to turn after a long day's drive. I would drive 500 miles and get to a customer and have to back in but the power steering would not let me turn the wheel. I had to rev up the engine to get it to turn and when I did it seemed to turn just fine so long as the engine was revved up a little. If I'm sitting still at idle it won't barely turn at all. I brought it into a shop and told them the issue. They called me back the next day and said they don't know why it was locking up but it's fine now so they drained and bled the system. I told them I wanted a new pump in it since this was the second shop that said it was fine and drained and bled it only for it to lock up on me after I drive it for a while. So they just replaced the pump as I asked and I picked it up, seemed to be working just fine. Drove about 340 miles, pulled into a rest area and noticed as soon as I was turning into the spot that the wheel had stiffened up since this morning. Sure enough when I stopped, the wheel would struggle to turn after about 1/4 turn. If I gave it some throttle it turned fine. What's going on with this #### thing and why do these shops keep claiming nothing is wrong?

 

Nope spotless. Only place there is oil is around the drain plug for the motor. Tightened that up already though.

 

So I need a steering box then. And 3 shops couldn't tell me that. Two were KW dealers, the other was a Power service shop in Indianapolis. I'll have too look into those now and get some prices. I'm about to start doing these harder jobs by myself. I also had a tractor air leak that I didn't know the location of and they claimed to have fixed it and tested it but nope, looks like I'll have to get my torch ready for frozen trailer breaks since I can't keep the tanks full at night with the truck off. I'll just watch YouTube and probably can get #### done better. Sorry but I've had it with these shops not knowing a bolt from a screw.

 

Right. That's why I explained to them what was going on because I knew it was fine when cold and only happened when it warmed up. But none of the shops listened to me and kept saying it's fine. That's why I told them this time I don't care if it's acting fine now, replace the ####ing pump. So they did. Elminiated that possible cause now and had to come to a forum to find out it was never the problem.