
This product is currently in the development stages, the information on this page will be updated as we progress.

Gearmaster
™Portal Axle
For
Nissan GQ and GU Patrol
Last Updated: 15/04/07
| These portal axles have been designed to directly replace the original Nissan GQ & GU Patrol live axle assemblies as fitted to all models from 1988 on. |
| At the present time the portal axle assemblies have
undertaken full stress testing and have an axle rating of 1530kg. The
Australia wide master engineers report is now complete, it
includes the necessary lane change testing required by West Australian
and South Australian authorities. All of the testing is being performed
with 35" tyres fitted. Yes, this means you will be able to legally drive your 4wd on
the road with 35" tyres.
Our prototype axles have been in operation since July 2006 and have travelled over 70,000km. For more details click here. |
| Ground Clearance
and Track 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. |
| Reduced Bump Steer
compared to suspension lifts 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
vibration 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. |
| Increased drive line
strength 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. |
|
Improved braking 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
Calliper
option Twin brake callipers can be fitted to the portal transmissions as they have been designed and machined with the necessary mounting points. |
| Lubrication 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. |
| Breather System 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. Tyre Size and Off set rimsThe portal Transmissions are supplied with a set of five 17"x8" steel rims with a 25mm positive offset, other versions are available. For correct steering geometry all of these rims must be fitted with 35" tyres. Steel 16"x8" rims are available with a 40mm positive offset, these rims are sold on an exchange basis as they are made from the original Nissan type which have had the centres removed and a new style fitted, these rims will cost extra. We can also supply 17"x8" alloy rims with a +50mm positive offset, the alloys also cost extra. Front Tyre Clearance (Control Arm Spacers)When fitting 35" tyres to Nissan Patrols it is necessary to move the front axle forward, this is to help the tyre clear the rear of the front guard when turning. Marks 4WD Adaptors manufacture and supply the required spacers with the portal axles. For more information click here. Rubber FlaresAs there is an increase in the vehicles track of over 100mm the tyres will protrude past the mud guards, to overcome this problem the portal axles are supplied with the necessary rubber flare and fixing screw kit. For more details click here. 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. Diff Centres 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. Steering Track Rod All Nissan front portal axle assemblies are supplied with a new heavy duty track rod and new ball joints. Free Wheel Hubs 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. Fully Floating Rear End 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. Portal Gear RatiosTwo portal transmission ratios are now available: 1.4:1 and 1.22:1 The 1.22:1 ratio is now available and makes the overall gear reduction 7% lower than standard when you allow for the 15% increase when fitting 35" tyres. This reduction helps to keep the overall conversion cost down as in most cases diff ratio changes are not required to achieve reasonable road speed. |
Various Gear Ratio Combinations With Portals Fitted
For optimum on road performance it is necessary to maintain the original engine RPM/road speed ratio. In a vehicle fitted with a manual transmission we recommend using 3.9:1 diff ratios with one of our new overdrive 5th gear sets, this combination with 35" tyres will only increase the engine speed by 50RPM at 100 kph. Alternatively 3.54:1 diff ratios with 35" tyres is perfect. Both of these ratio combinations will suit a vehicle fitted with an automatic transmission. The two combinations above are the only ones suitable for on road use. For more information on the 5th gear option click here.
If you intend building a competition vehicle click here for alternative ratios.
Speedometer Recalibration
After the portal axles have been fitted the speedometer will require
recalibration to allow for the change in axle gear ratio. The GQ-GU portal axle
kit is supplied with with one of our electronic tyre match boxes. Click
here
for more information. Nissan GQ Part Number is as follows:
PART NO. MFK1625GQ - Exchange Front and Rear Portal Axle Assemblies to suit Nissan GQ Patrol all models. $17,500 inc GST
The kit consists of: Fully Assembled and Reinforced Front and Rear Portal Axle Assemblies, New Brake Master Cylinder, New Disc Rotors, 2ltr of Synthetic Oil, Oil Hand Pump, 4 x Braided Brake Lines, Breather Hoses, Breather Manifold, Breather Filters, Breather Manifold Bracket, Front Control Arm Spacer Kit, Rubber Flare kit, Free Wheel Hubs, Electronic Tyre Match Box, 5 x 17"x8" steel rims (16" rims are exchange Nissan with 40mm positive offset and cost an extra $100 inc GST each). 4 heavy duty rear control arm bushes and bolts.
In this kit we supply a GU front end and a GQ rear end which has been widened to the same track as the GU. They are sold on an exchange basis for your original GQ axles.
Nissan GU Part Number is as follows:
PART NO. MFK1625GU - Exchange Front and Rear Portal Axle Assemblies to suit Nissan GU Patrol all models. $16,000 inc GST
The kit consists of: Fully Assembled and Reinforced Front and Rear Portal Axle Assemblies, New Brake Master Cylinder, New Disc Rotors, 2ltr of Synthetic Oil, Oil Hand Pump, 4 x Braided Brake Lines, Breather Hoses, Breather Manifold, Breather Filters, Breather Manifold Bracket, Front Control Arm Spacer Kit, Rubber Flare kit, Free Wheel Hubs, Electronic Tyre Match Box, 5 x 17"x8" steel rims (16" rims are exchange Nissan with 40mm positive offset and cost an extra $100 inc GST each). 4 heavy duty rear control arm bushes and bolts.
Fitting cost for the above is $1500 inc GST This includes labour to remove and refit the front and rear diff assemblies, fit new springs and shockers if required, fit the new brake master cylinder, braided brake lines and bleed the brakes, fit the portal breather system, supply oil for the diffs, fit the front control arm spacer kit, fit and balance your tyres on the rims supplied, fit the rubber flare kit, fit the tyre match box and calibrate the speedometer,
Engineers Report Australia Wide $795 inc GST
Ratio changes from your original diff ratio will incur the additional cost of the ring and pinions.
NOTE 1: An additional $110 inc GST will be charged for fitting each ARB Air Locker.
NOTE 2: An additional $110 inc GST will be charged for fitting each new Ring and Pinion.
Nissan GU Portal Axles (No Extras):
PART NO. MFK1625GUFR - Exchange Front and Rear Portal Axle Assemblies to suit Nissan GU Patrol all models. $14,500 inc GST
The kit consists of: Fully Assembled and Reinforced Front and Rear Portal Axle Assemblies, New Disc Rotors, 2ltr of Synthetic Oil, Oil Hand Pump, Breather Hoses, Breather Manifold, Breather Filters, Breather Manifold Bracket.
Optional ARB Air Lockers
PART NO. RD78A - Air Locker Front to suit Nissan GQ, GU Patrol all models. $1270 inc GST
PART NO. RD24 - Air Locker Rear to suit Nissan GQ, GU Patrol 11 bolt (H233) diff. $1210 inc GST
PART NO. RD70 - Air Locker Rear to suit Nissan GQ, GU Patrol 12 bolt (H260) diff. $1330 inc GST
PART NO. CKSA12 - Air Locker Compressor Kit (can't be used for pumping up tyres). $175 inc GST
PART NO. RDCKA - Air Locker Compressor Kit (can be used for pumping up tyres). $335 inc GST
PART NO. PUKT - Air Hose Kit. $62 inc GST
Optional Diff Ratios
Click here for ratio options
Optional 35" Spare Wheel Carrier
Click here for more information
Copyright © 2006
Marks 4WD Adaptors
Last modified:
August 13, 2008