We take a lot of things for granted in life, especially when it comes to the everyday objects we use, like our cars and their Tyres.
When going on a 4×4 trip, checking your tyre pressure is one of the most important things you need to do, taking the terrain into consideration. Although you might be more fixated on what you need to pack for the trip, your tyre pressure influences your vehicle’s performance.
The making and manufacturing of a 4×4 tyre are much more complex than you might think.
The rubber fitted to your 4×4 can make or break your vehicle’s performance, both on- and off-road. However, have you ever given thought to the extensive research and development that goes into producing and making a 4×4 tyre?
The six-step process
- Research and development process
A tyre comprises more than 10 components and the decision regarding the types of materials, rubber compounds and construction methods is its own science. Initial tests are conducted under controlled conditions in a laboratory before on-road testing commences.
Tread-pattern design is interesting to think about when it comes to off-road tyres. The general perception that the topography of the tyre is mostly for aesthetic appeal cannot be further from the truth. Every little edge, chamfer and block is there for a reason, and nowhere is this more evident than on off-road tyres with bold patterns.
The downside of an aggressive tread pattern is increased road and wind noise at speed, as well as a rolling-resistance penalty, resulting in increased fuel consumption. The general trend is for less-aggressive patterns to meet tyre regulations without losing off-road performance in the process.
- The process of production
The same method of tyre production is employed locally and internationally. The reason for this is a tyre – especially an off-road – is a complex item with many components, and so requires extensive human input and is an extremally labour-intensive process just to create a single tyre.
- Raw materials
Rubber compounds arrive in bulk at the extruders. They are heated and forced through a specific die creating a green rubber profile. The tread consists of three types of compound: the base, the cap and wing strips located beyond the tread shoulders. These three co-extruded compounds are overlaid to form a continuous assembly that is cut into specified lengths for the tyre circumference.
Although each tyre carries a barcode documenting its production history, paint of different colours is applied to the tread in thin stripes as a visual aid to distinguish between tyre designs. Sidewalls as well as tyre-reinforcement materials arrive in bulk rolls and must be cut to size and specified angles before being joined with the tread. Even the hoops of steel wire anchoring the ply and securing the tyre onto the wheel rim are created on site by winding steel wires in a pattern and enclosing them with more rubber.
- The assembly
A casing is made consisting of an inner liner, bead, apex, sidewall and, in some cases, reinforcement and shoulder pads. The casing is then expanded on a build unit, where the tread assembly is applied. The tyre slowly takes shape. No adhesive is used between the component layers, as the vulcanisation of the rubber during the curing process forms the permanent bonds.
- Curing and tread
The tyre is inflated with a bladder before it is heated internally with steam. Temperature and time for the tyre to set in its final form but it still resembles a racing slick with no tread. Then more heat is applied in an oven, where the tread moulds are clamped on the tyre from the outside, forging the rubber into the required shape.
Each tyre goes through a visual-inspection phase and then endures testing before it can leave the factory. This includes mounting it on a rim and testing natural balance at speed. After a few more tests are done, it then gets checked again and shipped off to your local tyre store.
Sand, Mud and Water terrain tips when driving a 4×4:
Choosing a gear that allows the engine to rev slightly high, allows you a safety margin in the event of deep patches. When you feel wheel-spin beginning, ease off on the accelerator; if you feel that you’re getting stuck, take your foot off the accelerator and coast to a stop. If you can, reverse; if not get some help. It’s no good trying to keep going as you’ll only get into deeper trouble and make any chance of recovery more difficult. You should avoid using the brakes.
You can reduce your tyre pressure as low as 1,2 bar on 4×4 vehicles but do bear in mind that any sudden turns may cause the tyre to roll off the rim. If your vehicle is fitted with a “diff lock”, be very careful when using this in sand as it can cause the vehicle to handle strangely.
There will, however, be times when you will become stuck. The first thing to do is stop. Take some time to work out why you’re stuck. Dig away any sand in front of the wheels and place items such as car mats, branches etc. under the wheels that will give you
Mud comes in various types, from thick, bottomless clay to the slippery surface mud found in forests. The key is reduced tyre pressure, a low gear to give enough engine speed, and momentum. Before you drive through any mud, take the time to look at the terrain and where you need to go. Better to get your shoes a bit dirty than just blasting into it and getting stuck. Look at the terrain around you — if it’s rocky, there’s a good chance that there’ll be rocks in the mud too.
No matter how much you are tempted, don’t change gear, as you’ll reduce the momentum of your vehicle and probably become stuck.
If you feel any wheel-spin, try easing off the accelerator to slow down the wheels and give them a chance to get traction. You can try to gently move the steering wheel from side to side to give the tyres’ sidewalls a chance to get a foothold. Don’t try to force the steering wheel in a direction, just hold the wheel gently and guide the vehicle in the direction that you want to go.
Should you become stuck in mud, stop and determine exactly why you are stuck. Getting unstuck normally involves digging. Clear mud away in front of the wheels and try to get branches or any other items that will give you traction under the wheels. Pulling away may also require some assistance in the form of a push or a tow rope.
Water crossing can be a dangerous and often deceptive challenge. A lot of problems can be avoided by knowing your vehicle: know how low your air intake is situated and let that guide you. For bakkies, don’t try anything deeper than the top of your tyre. As you approach rivers, take in the terrain.
Flowing rivers normally have a more stable base than standing water. Before entering the water, either disconnect the fan-belt or jam the fan with a towel or such-like to prevent the fan turning. This will stop the fan moving forward and damaging the radiator and prevent it from splashing water up onto the top of any electrical components.
Look at your exit point. When crossing flowing water, cross at an angle that is slightly against the flow – this gives you additional time if the water suddenly starts pushing the car, to either reverse or accelerate to the other side.
Once in the water maintain a steady speed don’t change gear, as the sudden loss of momentum when depressing the clutch will cause the bow-wave created by the vehicle to splash over the vehicle. Remember, if your vehicle stalls, don’t try to start it. Instead tow the vehicle out, remove the air filter and check for water. If the filter is wet, remove the spark/glow plugs and turn the engine over on the starter to remove any water.
If you need to sell your 4×4 or everyday car, we here at You Drive We Sell will be more than happy to help you with a quote!
All you need to do is fill out our form on the website and we will contact you!