To limit the strain on the tractor and the towing eyelet one are able with the hydraulic frame lock to transfer the weight to the tractor at the pulling moment when the load eases of the ground. This feature can be seen as a weight transfer cylinder that works in conjunction with the bogie blocking (interaction does not occur with sprung bogie) and provides a more stable loading and increased safety margin. With the frame lock the whole of the tractor is used as a balance when hooking.
Art. no 700628