Almost every modification to make our 4x4 vehicles more bush friendly involves some type of compromise, says Mic van Zyl.
An interesting aspect of representing a major 4x4 brand is how, quite often, there seems to be a wave of interest in a certain product and then it quietens down and another product suddenly enjoys the limelight. I’m convinced this is partly driven by social media and the keen interest many off-road enthusiasts take in their choice of hobby.
Recently, we’ve had a spate of enquiries about side steps and rock sliders. After speaking to many of these enthusiasts,
I can see there’s a misconception around side steps and rock sliders. More importantly, there’s an alarming lack of knowledge and understanding about side curtain airbags and how the fitting of aftermarket side steps or rock sliders can affect the correct operation of this critical safety device.
FIRSLY, THERE is a fundamental difference between the original aluminium and plastic side steps on a new vehicle and the sturdy aftermarket steel replacement ones. Typically, the original side steps are lightweight and look great – they’re designed to integrate with the design of the vehicle as a whole. They are also attached to the body of the vehicle as opposed to the chassis.
Their primary function is to assist with the ingress and egress of the vehicle. Secondary to this, they offer a small amount of protection to the side of the vehicle, particularly from road debris that gets flicked up by the front tyres. They do not, however, offer any significant protection from a ground strike when traversing rough terrain. They bend and buckle at the first sight of a proper rock.
Enter the aftermarket steel side steps and rock sliders. The fundamental differences are very heavy-duty design, construction and material compared to the original steps, as well as the fact that they are bolted onto the vehicle chassis with some heavyduty brackets.
In the case of a properly designed and manufactured rock slider, you can indeed slide over rocks with the weight of the vehicle without any damage to the vehicle sill. They don’t look anywhere near as good as the original steps but, for the serious off-roader, they are almost mandatory due to the protection they offer.
SO HOW DOES THIS affect your side curtain airbags? The sensors that control the activation of these airbags are similar to the sensors that control the activation of the frontal impact airbags. They measure G-force and activate accordingly. The original side steps are designed to not affect the correct operation of these airbags. Fitting a set of strong, solid rock sliders to the vehicle chassis will naturally change the dynamics of a side impact. In testing, we found that, with the aftermarket rock sliders, the side airbags deploy in any event.
So, no problem there. What does become a problem is that one can possibly have premature or unnecessary deployment of your side curtain airbags while clambering over rocks should you come down hard on the solid rock slider. I have personally experienced this in a Pajero that was fitted with rock sliders.
A good compromise are sidecurtain-airbag-compatible steel side steps. These can withstand rock impacts better than the original aluminium product but not to the extent of proper rock sliders. They are also attached to the vehicle chassis, but by means of engineered brackets that do not alter the correct working parameters of the side-curtainairbag system.
As always, almost all modifications we make to our 4x4 vehicles to get them more bush friendly involve some type of compromise. This compromise should, however, never put at risk the safety of you, your family, your vehicle or other road users.
Fitting a set of strong, solid rock sliders to the vehicle chassis will naturally change the dynamics of a side impact.