An axle assembly includes a first rail assembly, a second rail assembly and an open-section twist beam connected to the first rail assembly and the second rail assembly. The twist beam includes an upper wall, a lower wall and rear wall wherein the upper wall and the lower wall are connected by the rear wall to define an open portion of the twist beam where the upper wall and the lower wall are separated by a vertical distance. The open portion of the twist beam is forward facing. The axle assembly further includes a torsion bar that extends through and is connected within the open portion of the twist beam.

A wheeled work vehicle (1) comprises a forward chassis part (4) and a rearward chassis part (5) pivotally connected about a substantially vertically extending primary pivot axis (7) for steering thereof. A pair of forward ground engaging wheels (29) are carried on a forward suspension unit (32), and a pair of rearward ground engaging wheels (30) are carried on a rearward suspension unit (33). The forward suspension unit (32) is pivotally connected to the forward chassis part (4) by a pair of main forward transverse pivot shafts (63) pivotally coupled to the forward chassis part (4) by corresponding main forward pivot mountings (65). The main forward transverse pivot shafts (63) defines a main forward transverse pivot axis (59) about which the forward suspension unit (32) is pivotal relative to the forward chassis part (4). The forward suspension unit (32) comprises a pair of spaced apart trailing arms (35) which are joined by a torsion shaft (68) of tubular steel, which is rigidly connected to the trailing arms (35). The torsion shaft (68) defines a torsional axis (70), and permits limited upward and downward pivotal type torsional deflection of the trailing arms (35) relative to each other. The rearward suspension unit (33) is substantially similar to the forward suspension unit (32) and is coupled to the rearward chassis part (5) about a pair of main rearward transverse pivot shafts (87) in a similar manner as the forward suspension unit (32) is coupled to the forward chassis part (4).

[Object] Damage to a surface of a resin bush caused by press-fitting is prevented even when a configuration for positioning during welding is added. [Solving Means] A rolled collar (40) is a steel rolled collar into which a resin bush (90) is pressed-fitted, and which is joined to a joining member by welding. The rolled collar includes a main body part (50) formed in a hollow cylindrical shape, and a clinch part that joins both end surfaces of the main body part together by fitting. The rolled collar includes a notch part (70) formed by cutting off a portion of an annular edge (53) in the main body part. Here, a convex jig determining a position of the main body part at a time of welding is fit into the notch part. The rolled collar includes a cavity part (80) formed to be hollow from an inner circumferential surface side on a wall surface around the notch part to form a clearance (81) between the press-fitted resin bush and an edge portion (71) of the notch part on the inner circumferential surface side.

A twist axle assembly (20) of a vehicle includes a pair of trailing arms (22) and a twist beam (24) having a base portion (46) extending along an axis (A) between first and second twist beam ends (42, 44). The twist beam (24) includes a pair of side walls (48) extending downwardly from the base portion (46) and each disposed in spaced relationship with the trailing arms (22). At least one mounting bracket (54) extends from a first mounting bracket end (56) disposed in abutting relationship with a respective trailing arm (22) to a second mounting bracket end (58) disposed in overlaying relationship the side walls (48) of the twist beam (24) for allowing the mounting bracket to axially slip or slide along the side walls (48) of the twist beam (24) and provide for lateral or axial adjustment of the twist axle assembly (20) during the manufacturing process.

[Object] Damage to a surface of a resin bush caused by press-fitting is prevented even when a configuration for positioning during welding is added.

[Solving Means] A rolled collar (40) is a steel rolled collar into which a resin bush (90) is pressed-fitted, and which is joined to a joining member by welding. The rolled collar includes a main body part (50) formed in a hollow cylindrical shape, and a clinch part that joins both end surfaces of the main body part together by fitting. The rolled collar includes a notch part (70) formed by cutting off a portion of an annular edge (53) in the main body part. Here, a convex jig determining a position of the main body part at a time of welding is fit into the notch part. The rolled collar includes a cavity part (80) formed to be hollow from an inner circumferential surface side on a wall surface around the notch part to form a clearance (81) between the press-fitted resin bush and an edge portion (71) of the notch part on the inner circumferential surface side.

A trailer for towing by a power vehicle is provided and generally includes a frame and a tandem wheel assembly. The frame forms an undercarriage chassis and the tandem wheel assembly positioned under the undercarriage chassis. The tandem wheel assembly includes a rear wheel assembly and a front wheel assembly. An extension assembly is provided and moves the front wheel assembly between trailing position and a self-propelled position where the rear wheel assembly and the front wheel assembly are positioned to equally support the undercarriage chassis.

A trailer for towing by a power vehicle is provided and generally includes a frame and a tandem wheel assembly. The frame forms an undercarriage chassis and the tandem wheel assembly positioned under the undercarriage chassis. The tandem wheel assembly includes a rear wheel assembly and a front wheel assembly. An extension assembly is provided and moves the front wheel assembly between trailing position and a self-propelled position where the rear wheel assembly and the front wheel assembly are positioned to equally support the undercarriage chassis.

A vehicle comprising: a vehicle body; first and second wheel assemblies each having a rotation axis; first and second suspension linkages, each suspension linkage coupling a respective wheel assembly to the vehicle body to permit motion of the rotation axis of that wheel assembly relative to the vehicle body; first and second dampers, each damper coupled to a respective suspension linkage to constrain the motion of the associated wheel assembly by applying a damper force to the suspension linkage; first and second springs, each spring coupled to a respective suspension linkage; and a cross-vehicle linkage coupled between the first and second springs, the cross-vehicle linkage being configured to have: (i) a first mode in which the cross vehicle linkage prohibits the first and second springs from constraining the motion of the associated wheel assembly, and (ii) a second mode in which the cross vehicle linkage permits the first and second springs to constrain the motion of the associated wheel assembly.