steering problem

[tommildren]

Have had this happen twice on this trip but never before. Steering seems fine except these two times we pulled off the freeway and after a few ok turns steering got so hard that I almost couldn't make the turn. Both times I was applying brakes and very slow making a 90 degree turn and the steering gets very hard, after the turn it was ok again.
unit is a 2000 DSDP and was serviced before trip which included new hyd filters and fluid. I checked hyd fluid level in engine comparment tank and it's full. No leaks and don't see anything unusual under front end.
Anyone had a similar problem

["007"]

Can you have someone steer the wheel while your in back and see if you hear the pump wine or belt slip while turning the wheel.
Maybe you need new pump.

[jimkate]

If the problem began after having the hydraulic oil and filters changed, check that the oil level isn't too high. I'm not familiar with your tank, whether or not it's vented, but oil expands with heat. In an unvented tank, that can cause steering lock up. ???