Patent ID: 7192034

Claim:
An articulated dozer, comprising: a front chassis portion; a rear chassis portion connected to the front chassis portion via an articulation joint; a first A-frame; a second A-frame, a length of the second A-frame frame being approximately equal to a length of the first A-frame frame, the front chassis portion and the rear chassis portion, respectively suspended above the first and second A-frames; a first suspension cylinder having a first cylinder head end and a first cylinder rod end, the first suspension cylinder operatively attached to the front chassis portion and the first A-frame; a second suspension cylinder having a second cylinder head end and a second cylinder rod end, the second suspension cylinder operatively attached to the front chassis portion and the first A-frame; a first pilot operated check valve having a first check valve pilot line, the first check valve connected to the rod end of the first suspension cylinder, the first check valve pilot line connected to the second cylinder head end; and a second pilot operated check valve having a second check valve pilot line, the second check valve connected to the rod end of the second suspension cylinder, the second check valve pilot line connected to the first cylinder head end.