Patent ID: 7207575

Claim:
A tractor, comprising: a chassis; an engine mounted on the chassis; a pair of steerable front wheels; left and right rear wheels; a left rear suspension including a left rear suspension arm pivotally coupled to the chassis and a left hydraulic cylinder coupled to the left suspension arm; a right rear suspension including a right rear suspension arm pivotally coupled to the chassis and a right hydraulic cylinder coupled to the right suspension arm; wherein the left and right hydraulic cylinders are coupled to the suspension arm to transmit only longitudinal forces between their respective suspension arms and the chassis in a first tractor load state, and to transmit both longitudinal forces and torsional moment between their respective suspension arms and the chassis in a second tractor load state greater than the first tractor load state; wherein the left and right cylinders include a cylinder body, and a rod assembly slidingly disposed inside the cylinder body, the cylinder body including a first eye configured to transmit longitudinal forces to the respective left and right suspension arms in a first orientation, and to transmit to the respective left and right suspension arms both longitudinal forces and torsional moments in a second orientation; the first eye defines a spherical aperture and includes a sphere disposed inside said aperture, wherein the sphere is pivotable within said aperture, and further wherein the sphere includes a means for coupling the sphere to the respective left and right suspension arms, and further wherein the first eye further includes first and second eye blocks, and a means for coupling said first and second eye blocks together, wherein the first eye block defines a first hemisphere of said spherical aperture and the second eye block defines a second hemisphere of said spherical aperture.