What on earth is a Lokka I hear you ask?!
Well I need to explain how a 4wdrive system works; In a normal 2 wheel drive car power is sent to the wheels via drive shafts. That is pretty simple, until you think about corners – obviously the outside wheel on the axle has to travel further – which means the drive shaft needs to spin a bit faster. Basically there is some type of mechanism which allows the two drive shafts spin at different speeds.
This is all very good – obviously we need to go round corners! But on a 4wdrive car this could mean that if you come across a surface that doesn’t have a lot of grip you effectively could be in 2 wheel drive with only one wheel on each axle helping you to move forward – while the other two just spin.
So to make the most of the 4wd we needed to lock the drive shafts together in some way – but something that isn’t permanent to enable us to still go around corners! Having as much traction is important in our little trip, it will mean that speed and momentum are less important when trying to getting over difficult obstacles – which hopefully should reduce the risk of damage to the vehicle and terrain.
There are a few different types of systems, from new this series of Landcruiser came with cable differential lockers – basically there was a level (near the handbrake) which was connected to each differential – operating the locking mechanism. These systems are difficult to hold of second hand and the mechanisms would not work with large fuel tank.
The most well know after market option is ARB air lockers, similar switch design as the factory kit, but uses an air rather than a cable. Only reason I didn’t choose these is that they are expensive and have to be installed by a professional – which would add to the cost still further.
So, as I was buying some things from 4wdsystems anyway it made sense to choose their “Lokka” system – it is a much cheaper alternative with no cables, air compressors or holes to drill in the differential casing. I understand it is basically the same as a Lockrite or an Aussie Locker, just have different names in different countries. I decided to go for front and rear!
The Install; (This is the rear one for a semi floating rear axle. Front / fully floating rear axles are pretty similar but without the pins)
Open up the differential cover (mine was nice and rusty..) and this is what it should look like – you can see the small gears in the middle. Undo the centre bolt and remove the centre bar and spacer.
After removing the brake drums, push the drive shafts in and remove the little “C” shaped pins in the middle of the gears on the differential. The drive shafts should now just pull out.
Remove everything in the middle and should get all of this; (note the drilled spacers)
and an empty hole like this!
Here is the Lokka –
All separated out;
There are instructions that come with the lokka – so please refer to them for exact measurements
Put the spacers on the back of the drivers and install them on the drive shafts – like this –
Put grease on the gears (so they stick together) and put the small round spacers in – then measure the clearance to the centre bar. Take the small spacers out install the couplers and measure the clearance. If all the measurements are correct – finish the assembly. If not, you will have to adjust the thickness of the drilled spacers.
Once all the measurements are correct – put the springs in and it should look like this;
Once it is all together – all you need to do is test it!
So as you can see in the video below, when it is locked together – both wheel should turn together.
Giving the wheel a little nude unlocks it – enabling the right (or left) wheel to turn independently – you should be able to hear it click.