The 3 point lift and front end loader on that tractor should have two separate hydraulic systems, so the two issues should not be related. The front end loader should be powered by a pump that is mounted on the front of the tractor down below the grill that is powered via a shaft from the crankshaft pulley, and the reservoir should be inside the loader frame. The 3 point hydraulic pump should either be, depending on which transmission and PTO options it has, on the left side of the tractor as you're sitting on the seat at the rear of the engine near the flywheel, or inside the right side of the rear axle center housing, and the reservoir for the 3 point hydraulics is the sump of the rear axle itself.
The 3 point problem sounds like a stuck unloader valve, which is under the 3 point hydraulics top cover. The top cover is the large piece of cast steel that the seat bolts to and that also has the upper lift arms and 3 point control quadrant coming out of it. You are going to need to pull the top conver and remove the unloader valve and clean it with some extra fine emory cloth to get it unstuck. While you have the top cover off I would recommend doing a full R&R of all of the o-rings and seals iunder there as well as making all of the recommended control linkage adjustments that are in the service manual. If you do not have one, get yourself a Service Manual. You can eiter get an original Ford Service Manual or an I&T after market service manual. The I&T FO-31 manual covers the 3 cylinder 2000/3000/4000 series ag chassis models, but the 3 point hydraulics on your 4400 are the same as on the ag chassis 4000 model so it will cover what you need to do.
Which fluid and filter did you change when you said that the loader issue was better after you changed them? If they were in the rear axle under the top cover then that shouldn't have affected the loader at all. If it was the fluid in the frame of the loader and the filter inside the loader frame up on top of the bottom plate below the left upright of the loader frame then those were the correct fluid and filter changes. If it is still jerky after that then I would guess that either there is still gunk inside there that might be clogging tjhings up, or there are some internal seals or o-rings that are bad either inside of the cylinders or inside the control valve.
The 3 point problem sounds like a stuck unloader valve, which is under the 3 point hydraulics top cover. The top cover is the large piece of cast steel that the seat bolts to and that also has the upper lift arms and 3 point control quadrant coming out of it. You are going to need to pull the top conver and remove the unloader valve and clean it with some extra fine emory cloth to get it unstuck. While you have the top cover off I would recommend doing a full R&R of all of the o-rings and seals iunder there as well as making all of the recommended control linkage adjustments that are in the service manual. If you do not have one, get yourself a Service Manual. You can eiter get an original Ford Service Manual or an I&T after market service manual. The I&T FO-31 manual covers the 3 cylinder 2000/3000/4000 series ag chassis models, but the 3 point hydraulics on your 4400 are the same as on the ag chassis 4000 model so it will cover what you need to do.
Which fluid and filter did you change when you said that the loader issue was better after you changed them? If they were in the rear axle under the top cover then that shouldn't have affected the loader at all. If it was the fluid in the frame of the loader and the filter inside the loader frame up on top of the bottom plate below the left upright of the loader frame then those were the correct fluid and filter changes. If it is still jerky after that then I would guess that either there is still gunk inside there that might be clogging tjhings up, or there are some internal seals or o-rings that are bad either inside of the cylinders or inside the control valve.
