Please provide your tractor's exact model number.
Provide loader model number and also if it has a self leveling valve
There are two different hydraulic setups on M7040. Labelled Type 1 or Type 2
If your tractor has a cab there will be a label on the right lower door glass like this one.
How many rear remotes do you have? The tractors came with one and could have up to three.
Is anything currently plugged into a rear remote?
Do you have a third function valve for a grapple or similar?
Please provide more detail on the history of this problem. Did it happen slowly gradually getting worse or suddenly. Has any work been done on hydraulic hoses.
Do other hydraulic functions like power steering, 3 pt hitch and hydraulic shuttle if equipped work OK.
Check that a rear remote is not in a detent position..... i.e. make certain remote valves are in neutral/middle position.
Dave