I have the RK 55 and have the same issue with my bucket but mine started after a day of heavy use. My thought was I over worked it. My first observation was that one cylinder ( right one)extends before the other and remains 3/4" longer lifting it all the way up. I thought it may have been a cylinder issue so to check it I pulled both the left and right cylinders and swapped them. It did not change anything , still the same cylinder extending first ( right one) So far I could not find any reason why. My next thought was maybe there was a loose bolt. No such luck. My next thought was maybe I twisted something. I have no idea how to check for that as nothing stands out. I would love to rent a trailer and take it to the dealer to let them check it out but haven't been able to find anyplace that will rent an equipment trailer on a daily basis. Dealer subs out their hauling and the cost is over $1000 to pick it up and return it. One other observation I've made is that when I put it in the float position to back blade something it levels out and works great but other wise is almost 3" higher on the one side. My tires are fine, my hydraulic level is good. Not sure what my next step should\will be.