Posted in Defensive Driving, Safety

Diff Lockers Great Video

What are diff locks on my 4x4?

So what is this all about then?  Don’t I already have a 4 wheel drive?  Is someone just trying to sell me another accessory that I don’t need?  Well the interesting thing is that many more recent 4x4 vehicles already come with a factory fitted diff lock in the back axle.  It is generally operated via a push button depicting the four wheels of the vehicle with a cross or “x” in between the rear wheels.  So you don’t need to spend any more cash at all.

  Look for the button with X at rear axle

But not all vehicles have this feature, especially older models. The good thing is that if you decide that you do need them, then you can get them fitted via any of the big name 4x4 mechanical workshops dealing in “aftermarket” accessories and equipment.

So then we come back to our starting point question which was “what are they all about, and do I actually need them”? In a nutshell most standard 4x4 vehicles are in most cases more than adequate for what we need or more the case, actually use them for. We often prefer these vehicles because they can tow a greater weight, give us a better carrying capacity, have a higher seating position that provides better vision and are significantly stronger and safer in their design for use on unsealed roads. 

So we can see how even with our diff locks engaged and drive to all four wheels, the Toyota is still stuck.  Being a heavy vehicle in soft ground, it has actually "bottomed out", so it actually has the diffs and or chassis lodged in the dirt. It is difficult to get traction in these situations as the tyres are full of mud and totally unable to get any grip in the slimy mud. The weight of the vehicle is also creating over 3.4 Tonnes of resistance.  A winch was used and the recovery undertaken quite easily in the end.

Then of course they have a 4x4 capacity in either high range and or low range which allows us to tackle more interesting terrain such as beach driving (where permitted), riverbeds, inland dune tracks, boggy tracks and very loose rocky climbs or descends etc. This is where traction, vehicle capacity, approach angles, tyre types and driver skills come into play. While our 4x4 vehicle may handle everything that we are comfortable subjecting it to, it is often a fine line between getting through and getting stuck.  4X4 training will teach you how to use diff lock

This is where a training course can assist you in gaining a better understanding of your vehicle, its capacity and features (and after market accessories), terrain types and situational issues that can occur across our magnificent country. Anyway, I digress, so without diff lock capacity once your vehicle is on loose ground, slipping in mud or if the ground is so uneven that one or more wheels are no longer touching the ground, we generally lose all forward, or backward momentum. In short we are bogged, stuck, not moving etc.

This is all due to the fact that once lets say our left front wheel has left the ground or is sitting in mud and starts spinning, the wheel on the opposite side to that basically stops, this is because the diff just keeps spinning the wheel that has the least resistance. So even though we have a 4x4 we have now lost traction at the front two wheels. While you still have the back wheels pushing you, it may not be enough to get you out of the situation you are in. This can also occur with the rear wheels and if one is slightly of the ground it also will be spinning with the wheel on the ground doing nothing.

Now then, if we were to engage our factory fitted or aftermarket diff lock in the rear, then we would also be getting positive drive to the wheel that is still on the ground thus increasing our chances of maintaining momentum. But as always this is not the ultimate “I will never get bogged again” situation, because as you can quite clearly see in the video, this Toyota has both front and rear diff locks and all four wheels are turning trying to gain some traction, but the ground is soft, slippery and as such unable to move, so its bogged!

Heavy vehicles will sit down firmly on the ground, the underbody may also be lodged into the soil as well thus adding to the resistance and there is only so much those tyres can do in trying to move the car forward.  So do diff locks actually help the car to be a more capable 4x4, “yes they do” , does it mean you will never get stuck again, “no it doesn’t”, are there many situations that they will assist to get you through were without them you would be struggling “absolutely’!  Next 4WD course in Darwin

Given that there are so many variables when we go out 4x4 driving, many different vehicle types, tyre configurations and driver skills/knowledge, there is nothing that will ever make you invincible. Diff locks are just another feature that we have up our sleeve when low range, or reduced tyre pressures, or “chunky” tyre treads or our amazing driving skills need that little bit of extra assistance! Drive safe and well.

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