When I raise / lower the FEL, broom, or steer the moving Kubota L2800 tractor I have a shaking or shaking sensation. It seems to decrease if I run the engine at a higher speed. I bought the tractor new in 2006 and it has 200 hours, so I don’t use it much, but I run it for at least a few hours every month – more in the summer.
I did the 50 hour maintenance, but I am not a tractor mechanic. So I only look for suggestions before taking it to the dealer for repair.
Check the rubber suction hose on the right foot. It is about 8 “long and has some curves. They crack and allow air to enter the line. This will cause what you are describing. The one in my L3400 has a crack and I bought a new one that I have to install.
I bet a dollar it’s the suction hose, remove it and wrap some of that silicone tape around it until you can get a new one. I have one around here somewhere still in the package.it is some kind of L-shaped hose, and usually painted gray from the factory, about an inch across maybe 1 1/4 to the sight … but you may not have thought that a hose because of the paint … aboard your right foot and of course a little ahead of your foot. Known trouble maker, and an easy fix.