I have a 2305 with the independent (hydraulic lift), and have not been able to cut very high at all. I have searched the site for answers and do not have a problem with adjustment knob as it turns easily. In the pictures below I think my problem is the rockshaft cylinder. In the first picture (from another 2305 on the web) the rockshaft support has one hole. In the second picture (my 2305) there are two holes, and the hydraulic arm is in the second hole. This casues the whole arm to lift too high, and the rockshaft arm bumps the above platform. I have to the the P bolts almost all the way out, so they do not hit the stops, and then it lowers about 2 inches before it stops at the transport height. The thrid pciture is from a slightly different angle. I hope this is making sense. I tried to move the arm the first whole, but then the spring behind it is binding. Any ideas?