I've been reviewing threads for hydraulic oil heat warning problems and have seen very similar queries but not with a brand new tractor. I do not live close to a dealer so I am trying to figure it out.
My new 5065 now has 35 hours and around 23 hours the hydraulic oil hot warning light started up. I received the new tractor with backhoe and frontier root grapple attached. I did 12-15 hours of work with no heat light warning. After I took off the backhoe and switched to a bushhog, the light came one after a few hours of work. Since then, it's been coming on in 45 minutes unless I am just driving it or using the grapple lightly. I checked troubleshooting in the manual and the oil level was slightly low but I added more to fill and the light is still coming on. I have not checked any filters except to see no leaks. The oil looks new and perfectly clean -no bubbles- in the level glass.
I called my dealer to ask if I should have connected the two (male and female) lines after detaching the backhoe. He said yes but when I did that the rockshaft quit working entirely (plus I had to swap out the male hydraulic fittings as the two on the tractor would not mate because male was too long). So I unplugged them and replaced dust caps and left lines hanging. Then rockshaft worked perfectly. I told him what happened and he said it might not be the same with smaller models he deals with. The backhoe manual does not specify what to do with the lines in a 5000 series. Maybe that's something? Is there some other reason the rockshaft would instantly quit working when I plumbed them together?
Also, is it normal for the rockshaft to only work when the SVC control lever is engaged? When it is, it hisses. So I have to turn it on and off when I want to raise rockshaft. Seems odd.
Dealer said to check the air intake but I did it all looks clean. Everything is still lot-new looking inside except a little dust. It has done some heavy work already in these first hours but not much.
Another thing I have noticed is that the grapple hydraulics in the boom frame seem to be "hissing" when I'm not operating joy stick. sort of like the sound when you raise rockshaft into max height and hold. I don't know what could be causing this sound. When I move stick the sound stops. Maybe this has something to do with it? I've inspected lines and connections, everything looks spiffy clean and dry.
Please help I have a ton of work to do.