60XT drive motor whine

[JoeCamel]

I have a 2003 60xt with low (680) hours so plenty of sitting that I changed hydraulic fluid (10w-30) last year and now the final drive is noisy as you work it. Sounds like Shelby Stangas swamp buggy on AX MEN if you have seen the show. Everything seems to operate properly, gets jerky if you run the engine too fast and work to get the oil hot. Does not overheat just normal temps. Is the pump failing? filter need cleaning?
Only leak on the drive is direction control shaft is seeping a little.
Any and all suggestions are welcome, thanks

 

[Gearclash]

Did you add HTO when you did the hydraulic oil change?

I no longer use 10-30 + HO in favor of a top shelf hydraulic oil.

 

[JoeCamel]

No, Case says not needed and not for sale. ZZDP was the anti wear part of the additive. It sounds like an old Ford power steering pump in a parking lot mostly if the left drive side is full forward or back but is present on the rit side to some degree as well. I wonder if CAT additive would make a difference
The hotter the oil the louder the whine

 

[Gearclash]

My knowledge of the 60XT is somewhat limited. I believe the hydro pumps and motors both are of the axial piston type. My thought is that a problem with them would generate more of a growl than a whine. I would assume there is a gear pump charging the hydro pumps and I wonder if that is where the whine comes from.

 

[JoeCamel]

My knowledge of the 60XT is somewhat limited. I believe the hydro pumps and motors both are of the axial piston type. My thought is that a problem with them would generate more of a growl than a whine. I would assume there is a gear pump charging the hydro pumps and I wonder if that is where the whine comes from.

I have a set of microphones so when I get time maybe I'll pinpoint it. I got all the dirt moved and seed out yesterday and things are slowing down for winter letting me work on equipment. Thanks