I took the tractor out of the shed today to do some barn cleaning. When I have the hydro pedal down half way or more it makes a slight whinning /squealing noise. It only does it when the pedal is about half or more. Its hard to pin point, but it sounds to be around the middle of the right side under neath. Like in front of the hydro pedal. It kinda of sounds like when a hyd. pump is low. I checked the dip stick behind the seat and the level is fine. It was about 30 degrees today. I have had it out in the upper teens and no problem, so I don't think it was from the cold. Any suggestions would be greatly appriecated.