Extendible axle member for the rear of an agricultural harvester

An extendible axle member (146, 148) for an agricultural harvester (100), the harvester having a chassis (107) supported on two driven front wheels (122) and two driven and steerable rear wheels (124), the rear wheels (124) being supported on a rear axle assembly (128) that includes a central axle member (136) supported on the chassis to pivot about a horizontal and longitudinally extending axis, the central axle member (136) including left side and right side outer axle members (142, 144), each of the left and right side outer axle members (142, 144) being configured to telescopically receive and support the extendible axle member (146, 148), the extendible axle member (146, 1481 comprising an elongate telescopic portion (400) having a generally rectangular shape defined by horizontal top and bottom sidewalls and two opposing vertical sidewalls, characterized in that each sidewall of the sidewalls meets each sidewall of two adjacent sidewalls at a beveled corner of the generally rectangular shape, each of the four beveled corners defining a bearing surface (252, 254, 334, 336), the four bearing surfaces (252, 254, 334, 336) being elongate, planar, and disposed at an acute angle to both the vertical and the horizontal, and further wherein said four bearing surfaces (252, 254, 334, 336) are disposed to communicate substantially the entire load applied by the extendible axle member (146, 148) to the outer axle member (142, 144).