John Deere 455 steering problem

[Maarten80]

I have a John Deere 455. When I have been mowing for about 30 minutes, my power steering goes out. The hydrostatic forward and reverse still works. I have no leaks; it's full of Trans oil. What is the problem that my power steering goes out and not working?

 

[joecdeere]

I have a PDF of the tech manual you're welcome to, sounds like it's time to do some reading!
Shoot me your email if wanted
Joe

 

[Maarten80]

I have a PDF of the tech manual you're welcome to, sounds like it's time to do some reading!
Shoot me your email if wanted
Joe

Hello Joe, i have send my mailadress to the private message.
what do you think is the problem?