Nissan Patrol 4x4 (Africa)

Hi Peter, I have a set on my vehicle. I believe they work with cams and will only lock if you apply a torque through your front diff. They will disengage on an overun. The other day when I had my rear propshaft refurbished I rolled my vehicle down my driveway a bit in order to do some work. Unfortunately, the auto hubs disengaged so the hand brake no longer worked. I ended up sitting in the sun for an hour with my foot on the brake until my daughter woke from her afternoon nap. Thy shalt not wake a sleeping child with the sound of a diesel engine!

Jy moes maar die Patrol in 4H of 4L gesit en gery het dan sou die voorste hubs weer ingeskop het en jou Patrol was dan frontwheel drive!

No, you should simply have switched the autohubs to "LOCK".

Peter Connan wrote:
Alan the simple fact is that at R20k I cannot afford an ARB, although I would personally have preffered it. My car is only worth 90-100K anyway, so to spend another 1/4 would not make a lot of sense.

Thanks guys
Peter

Lot of dudes build 4x4s/hot rods/road race cars/rally cars/other cool stuff where the value of the modifications is many times the "hull value" of the car they modify. So if you plan to keep this car, don't let the current value of your car stop you.

The main car parts that constitute a 4WD are the differentials (front and rear) and another is the transfer case. In addition, to this system, there is a part-time system in a vehicle, which has locking hubs as an important component. Both these systems have innovative and advanced electronics which results in enhanced performance.

What are Locking Hubs

Each wheel in a vehicle is essentially bolted to the hub. Locking hubs, a.k.a wheeling hubs, are basically an automobile accessory which is fitted to almost all the 4 wheel drive vehicles (4WD). The function of locking hubs is to allow the front wheels to get disengaged from the front half shafts in a car. If locking hubs weren't a part of a car, you would see all the 4WD vehicle's front wheels turning the front half shafts, which in turn would also turn the front drive-shaft and differentials of the vehicle. Thus, locking hubs are extremely necessary because they stop the spinning of differential, drive-shaft and half-shafts present in the car. This action practically saves a lot of wear and tear on the car components. Plus provides a quieter operation, less vibration and improves the overall thermal efficiency or fuel efficiency of the vehicle.

Well, in earlier times, manual locking hubs were used where in the driver literally had to get out of his truck or 4WD and manually turn on the knob present on the front wheels until the hubs were locked completely. The paragraph stated above, discussed the automatic systems of locking hubs, which are comparatively a recent trend. Herein, the driver of the four-wheel drive needn't get out of his vehicle, instead the system automatically gets engaged when the car is in motion.

Often seen that, 4WD vehicles, particularly the heavy-duty 4x4 trucks, do not have a center differential and hence the traction is limited in 'em too. They are called 2WD vehicles known to have an inactive differential and front axle present in them.

Why are Locking Hubs Vital

Locking hubs are necessary because when they are switched suitably, the front wheels of the drive train turn systematically. Moreover, locking hubs have a peculiar advantage in 4x4 vehicles because of its 'automatic factor'. The best part about locking hubs is, the driver doesn't need to leave the car to activate the 4WD or doesn't need to drive the car in 2WD with front axle engaged.

If one considers the example of locking hubs for jeep, the hubs present in jeeps, literally facilitate an excellent propelling power in the vehicle. So all those who own a jeep and are planning to go for an adventure in the toughest terrain, you can rely on these vehicles because they are specifically designed for mountainous adventures.

How do Locking Hubs Work

No 4x4 vehicle is complete without the presence of a locking hub. They are small sized dials located at the front wheel of a 4WD vehicle. It's vital to know how locking hubs function differently in a 4WD and a 2WD. There is an axle split half in half (right and left) both of them work separately, ie, they spin individually. There is a drive from the rear axle in a car that helps to push both these axles in the direction you steer. Well known as 2WD system. You can't put the car into 4WD when these axles are unlocked.

Now speaking about the 4x4 vehicles with automatic locking hubs, the process is quite simple to understand. In a four-wheel drive car, the shift lever is simply moved into the required position. This action of changing gears generates an inertia and locks the hubs conveniently. Herein, the locking hubs are actually connecting the two half in half axles to the drive plate locking them together as one combined unit.

In conclusion, there is one drawback which is often noticed, besides the benefits and advantages of locking hubs in vehicles. There can be a possibility for locking hubs to get damaged or broken due to severe terrain conditions and unsound roads. In such cases, locking hubs 4x4 becomes useless and the vehicle gets stranded in one place.