Is your BX 50,60 or 70 Series Tractor Hydraulics up to par?
Bucket not lifting or Backhoe not digging like it should?
Maybe you added a grapple and a few extra pounds to the bucket and now it does not lift as much or the hydraulic pressure relief valve spring is getting weak. It may have been set too low right from the factory.
Here is a low cost way to check your hydraulic pressure and bring it up to specs or boost it a little to get some more lift and digging capability. The kit comes complete with a high quality liquid filled Grade (A) 3000 lb pressure gauge with female quick coupler complete instructions and an assortment of Genuine Kubota pressure relief valve shims.
You should have this in your Kubota tool kit. Pressure should be checked at every service interval as the spring tension will change over time and it gets weaker not stronger.
All gauges are tested before shipment on a known 2000 PSI source to ensure accuracy. Check your manual to see what the hydraulic pressure should be, then you can adjust it as necessary.