A portal unit of the present invention includes a deceleration gear train and a housing. The housing includes an inner side wall that is formed with an input opening at a position above a rotation axial line of a driving wheel, an outer side wall that is formed with an output opening at a coaxial position with the rotation axial line of the driving wheel, and an intermediate wall that connects peripheral edges of the inner side wall and the outer side wall. The inner side wall is provided, at a radially outward position of the input opening, with mount bolts for the suspension unit. The mount bolts each include a shaft portion protruding inwardly in a vehicle width direction.

A mounting system for a portal lift assembly of an off-road vehicle includes a housing having a rear wall, a front wall, and a side wall. The rear wall includes an opening to receive the end of one of the vehicle's axles, and the front wall includes an opening to allow an output shaft to extend outward from the housing. The rear wall also includes an integral mounting brackets effective to mount the box to an upper A-arm to the rear wall, and a lower A-arm to the rear wall.

An apparatus and methods are provided for a portal spindle assembly for a vehicle front suspension. The portal spindle assembly comprises a spindle portion that is rotatably coupled with upper and lower connecting arms. A leading-edge portion is rotatably coupled with a steering rod-end joint, such that moving the steering rod-end joint rotates the spindle assembly with respect to the upper and lower connecting arms. An inboard case and an outboard case support a pinion gear assembly that is meshed with an output gear assembly for communicating torque from a constant velocity joint to a front wheel coupled to the output gear assembly. The pinion gear assembly is aligned along a pinion axis disposed at an angle with respect to a hub axis of the output gear assembly. The angle facilitates a suspension geometry that provides a camber change of the front wheel that eliminates a change in track width.

An adjustable portal box assembly for selectively mounting a wheel to an off road vehicle in either of two positions. The assembly includes a mounting plate mountable to the suspension of an off road vehicle, and a portal box is mountable to the mounting plate. The portal box includes an input shaft opening for an input shaft, and an output opening for an output shaft. The portal box is mountable to the mounting plate in a first position in which the output shaft is positioned to extend the wheelbase relative to the input shaft, or in a second position in which the output shaft is positioned in vertical alignment with the input shaft.

A portal gear box assembly effective to lift and change the gear ratio of a wheel of an off-road vehicle includes a housing, an input gear sub-assembly, an output gear sub-assembly, and an idler gear sub-assembly effective for linking the input gear to the output gear. The input gear sub-assembly includes an input gear, the output gear sub-assembly includes an output gear, and the idler gear sub-assembly includes at least one idler gear and at least one removable adaptor effective for holding the idler gear in either a first position or a second position different from the first position. The sub-assemblies may also include bearings to facilitate movement of the gears.

A portal box assembly for mounting a wheel to an off road vehicle in a lifted and extended wheelbase position. The assembly includes a portal gear box having an input shaft opening for an input shaft, and an output shaft extending from an output shaft opening. The portal gear box also includes a set of gears effective to transmit power from the input shaft to the output shaft, and optionally to reduce the gear ratio. The assembly is mountable to the vehicle in an extended wheelbase position in which the output shaft is positioned below and forward of the input shaft when the assembly is used to mount a forward wheel, and in which the output shaft is positioned below and rearward of the input shaft when the assembly is used to mount a rear wheel.

A portal gear box assembly for an all-terrain vehicle includes a sealed portal gear box housing having an interior housing space that contains a set of gears for linking an axle to an output shaft. An expandable space is in fluid communication with the interior housing space, and is adapted to allow pressurized fluid contained in the interior housing space to flow into the expandable space, thus expanding the volume of the expandable space and reducing the pressure within the interior housing space. The expandable space may be provided in the form of a bellows whose volume can be changed by expansion or contraction of a fluid contained therein. A fluid is contained within the portal gear box housing and within the expandable space.

The expandable space may be mounted externally to the portal gear box housing, and may be connected to the portal gear box housing by a conduit effective for allowing fluid to pass between the portal gear box housing and the expandable space. The expandable space and its connecting conduit are effective for allowing air to flow from within the portal gear box housing to the expandable space when an increased air pressure within the portal gear box is encountered, thus mitigating against a build-up of air pressure within the portal gear box housing.

A portal gear box assembly for an all-terrain vehicle includes a sealed portal gear box housing having an interior housing space that contains a set of gears for linking an axle to an output shaft. An expandable space is in fluid communication with the interior housing space, and is adapted to allow pressurized fluid contained in the interior housing space to flow into the expandable space, thus expanding the volume of the expandable space and reducing the pressure within the interior housing space. The expandable space may be provided in the form of a bellows whose volume can be changed by expansion or contraction of a fluid contained therein. A fluid is contained within the portal gear box housing and within the expandable space.

The expandable space may be mounted externally to the portal gear box housing, and may be connected to the portal gear box housing by a conduit effective for allowing fluid to pass between the portal gear box housing and the expandable space. The expandable space and its connecting conduit are effective for allowing air to flow from within the portal gear box housing to the expandable space when an increased air pressure within the portal gear box is encountered, thus mitigating against a build-up of air pressure within the portal gear box housing.

A portal gear box assembly for an all-terrain vehicle includes: a portal gear box housing a set of gears and linking an axle to an output shaft; a lubricating oil contained in the gear box; and a fluid circulation loop that circulates a cooling fluid to a cooling location outside the gear box. The cooling fluid may be a lubricating oil. The fluid circulation loop may include a pump and/or a filter. The cooling location may pass the fluid through a structure such as a radiator or other cooler. The circulation loop and/or any radiator/cooler, filter, or pump contained therein, may serve a single portal gear box, or may serve two or more portal gear box assemblies.

A portal gear box assembly for an all-terrain vehicle includes: a portal gear box housing a set of gears and linking an axle to an output shaft; a lubricating oil contained in the gear box; and a fluid circulation loop that circulates a cooling fluid to a cooling location outside the gear box. The cooling fluid may be a lubricating oil. The fluid circulation loop may include a pump and/or a filter. The cooling location may pass the fluid through a structure such as a radiator or other cooler. The circulation loop and/or any radiator/cooler, filter, or pump contained therein, may serve a single portal gear box, or may serve two or more portal gear box assemblies.