This could go in Hydraulics but ultimately it was mechanical bolts loose so it goes here.
Bucket started dumping by itself faster with a heavier load. Oh yeah 2007 machine bought new Just coming up on 300 hr oil change. I have a diverter valve on it Fasse. In fact my installation is on their web site.
The joystick handle was loose , I pulled off the cover and tightened the nut holding the handle on. The handle was still sort of goofy loose but I thought it was sort of normal. Everything worked except for the curl droop. So I read Jinman's excellent technique for isolating cylinder bypass issues. But I have a diverter valve so first I had to get it out of the circuit.
My install allowed for quick removal 2 hoses off replaced by caps on tees. The two more hoses swapped back and two plugs. All jic so pretty easy. Still had the problem. I was very doubtful of cylinder bypass , too new, and so got out my manuals and started reading. Just to increase my knowledge . Turns out there are check valves in the joystick valve, that was good to know. I thought one might be hung up on a piece of dirt. I pulled off the big cover over the valve and the check vlaves are under a set off steel pipes. Not conducive to removal. While I was looking at this jumble of pipes and thinking about the way to check cylinder bypass I notice a bolt on top of the valve backed way out. It held the swivel ball joint that actuated the curl cylinder. Two adjacent bolts were down tight. Tightened the bolt. Now I remembered how tight the handle was supposed to be. Ran the bucket around for a while lock to lock. Problem went away. Put the diverter valve back in. Problem did not return. Whewww. It is not always seals and cylinders.