73 John deere 830 hydraulic question

[2006gmcdmax]

I have a 73 John deere 830 3 cylinder diesel. I am experiencing some hydraulic problems. The pump sounds like it is whining but lifts great sometimes it will hesitate alittle lift hesitate alittle more then pick all the way up. What could be going on the filters need changing/ cleaning new hydro fluid or what?

 

[murphy1244]

Seems time for a oil and filter change.

 

[2006gmcdmax]

Yeah because it lifts good is the filter covered by a door with three bolts

 

[Tx Jim]

Hyd oil filter is on RH side in a cup held on by one bolt pointing "UP" located very close to screen that needs to be checked/cleaned. AR75603 FILTER ELEMENT