The portal transmissions have a vertical offset of 101mm/4", this 101mm lift raises not only the body and chassis it also lifts the differentials by the same amount. With the addition of 35" tyres the total increase in ground clearance is approximately 150mm/6" over standard.

When 35" tyres are fitted, the differential to ground clearance is equivalent to having a standard live axle fitted with 43" tyres.

The portal transmissions increase the track by 100mm per side. A combination of 25mm or 50mm positive offset rims fitted with 35" tyres are used to correct the steering geometry. These rim combinations give an overall 150mm or 100mm increase in the vehicles overall track. Both rim offsets have undertaken the lane change tests are included in the master engineers report.

Before   and after 

A suspension lift is not necessarily required, at best a moderate suspension lift of around 25mm to 50mm is all that is required when using this system. The control arms, and pan hard rods remain virtually flat.

Some advantages of minimal suspension modifications are, better handling due to no increase in bump steer. A softer ride can also be experienced with virtually flat control arms. Better tracking due to, unchanged caster angle.

Improved articulation is also experienced due to the increase in the vehicle track.

Drive line vibrations are a common experience when hi lift suspensions are fitted. With minimal or no suspension lift along with reduced drive line angles no drive shaft vibrations are experienced. This is due to the universal joints operating within their designed operating range.

The torque load which is normally exerted on the differential, axles and constant velocity joints is transferred into the portal transmissions, the amount of load transferred is proportional to the gear ratio used in the transmission. The gear reduction of 1.4:1, offers a load reduction of 40%.

The 40% gear reduction offers this same percentage increase in strength to all of the transmission components from the CV joints back to the engine.

All portal assemblies are supplied with a new smaller bore brake master cylinder for increased line pressure.

ADR approved braided brake hoses are also supplied.

New disc rotors are fitted and the brake callipers are reconditioned.

Twin brake callipers can be fitted to the portal transmissions as they have been designed and machined with the necessary mounting points.

Oil is used for lubrication and is easily checked using the filler/level plug fitted on the differential side of each portal transmission. A drain plug is also fitted on the same side for ease of servicing.

Each transmission holds approximately 400ml of oil. The oil supplied with the portal assemblies is high quality synthetic.

The portal Transmissions are equipped with external breather ports to allow hoses to be fitted. The portal axle assemblies are supplied with breather hoses, manifold, and filters.

GQ Patrol Portal Axles

To fit portal axles to Nissan GQ Patrols the rear axle housing must be widened to make it the same length as the GU Patrol. We now manufacture the necessary components to make this possible.

The front axle assembly must be replaced by one from a GU Patrol. Some of the advantages of upgrading are: wider track, larger brakes, stronger king pin/swivel housing as the bearings are further apart and the housing is much stronger. The other advantage is much larger/stronger CV joints.

The rear diffs in GQ and GU Patrols come as either the smaller H233B with 33T spline axles or the large H260 diff with 37T spline axles. Either of these diffs can be built into a portal axle. Please NOTE: Fewer diff ratio options are available for the larger H260 Diff.

All Nissan front portal axle assemblies are supplied with a new heavy duty track rod and new ball joints.

The front portal axle assemblies are fitted with AVM free wheel hubs. The hubs are not the standard Nissan type, the output axle shaft from the portal is much larger than the original Nissan. To accommodate the larger shaft we have manufactured a new centre spline section for the hub. If the vehicle is to be used solely for off road events such as rock crawling the free wheel hubs can be replaced with the rigid driving flanges which are used on the rear portal axle. 

All rear portal axle assemblies are full floating which means the rear axle no longer supports the wheel directly. All four wheels are supported using standard Nissan front, wheel hubs. The hubs are supported on a stub axle which is made from 4140 alloy steel, all four stub axles are the same.

The inner wheel bearing is a standard Nissan type while the outer bearing is one commonly found in a Toyota. The Toyota outer wheel bearing was selected because of its larger bore size which allowed us to fit the larger output axle.

1.4:1 and 1.22:1