I am a novice when it comes to tractors and asked a question awhile back about the lifting height of my 3pt hitch. After a brief discussion, it appeared to me that it was working fine. Then yesterday, I was working a PHD and for most of the day it was only 2 to 3 inches off the ground at full lift. Then all of a sudden I was able to get it 12 to 14 inches off the ground. I went around back and saw the triangular item in the first picture as it is. After looking at it it appears to attach to the upper 3pt arm like in the second photo and is held in place with a C clip on a post. This appears to be some sort of adjustable governor, if you will, to stop the 3 pt from lifting to full height. Is this what it is? And if so, why would you limit the height it can lift? My tractor is a JD 4300.