Things to know before you drive on dirt

Here, we’re going to focus on dirt and gravel roads, which can vary in quality and be a very different proposition to driving on sealed city roads. As such, they require an equally different approach to driving safely.

Four Wheels vs Two Wheels: Know Your Vehicle

First up, let’s talk about your vehicle. Four-Wheel Drive (4WD) or All-Wheel Drive (AWD) setups are going to handle unsealed roads much more safely than a Two-Wheel Drive (2WD), particularly when encountering loose surfaces, or handling corners or hills.

If you’re in a 4WD or AWD, consult your owners manual and ensure you’re familiar with how to switch between 2WD and 4WD modes. In modern vehicles this should be a straightforward, automatic switch - but older cars may require you to stop the vehicle completely and manually engage the front hubs. Note that in high-traction areas you should avoid engaging 4WD, particularly at high speeds, as it could damage your vehicle.

A 2WD vehicle will be able to navigate some dirt roads but the muddier it gets the more difficult it will be to drive, and the same goes for loose gravel. Front-wheel and rear-wheel 2WD cars will perform differently - on loose surfaces, generally front-wheel drive vehicles will be more predictable.

Be Prepared

When it comes to driving on dirt and gravel roads, your tyres are one of the most important parts of a safe journey. Wider tyres with chunkier tread patterns are going to provide you with better traction.

Tyre pressure is equally if not more important. Drive over long distances with over-inflated tyres and you run the risk of punctures, excessive wear and tyre and an uncomfortable ride to boot. As a general rule of thumb, the worse the surface the lower the pressure required. Gravel roads in good condition might not require you to drop pressure at all, but driving long distances on rough gravel should see you lowering the pressure down to between 26 and 30 psi (pounds per square inch), and for muddy surfaces as low as 20 to 25 psi. Remember that all cars and conditions will be different, and you may need to see how the car is handling after reducing pressure.

If you’re going to be travelling long distances, or regularly driving on dirt roads, consider taking a small air compressor as well as a tyre pressure gauge. Be prepared to be able to fix small punctures that may occur, and consider carrying a second spare tyre if you can.

Check your seals. Dust can and will get in anywhere if you let it (more on that later). Old or damaged seals might only let in a small amount of air, but that can mean an unpleasant amount of dust over a long journey.

Your windscreen wipers might be working overtime, so make sure your wiper blades are in good condition and that you’ve got plenty of wiper fluid.

Lastly, check weather conditions and if there’s rain on the way consider what that might mean for your journey. A dirt or gravel road can become muddy and slippery after a downpour, and some roads could be closed altogether because of the danger they pose when wet.

Out On The Road

The first thing you’ll notice about driving on dirt and gravel roads are the corrugations in the surface. Corrugations are bumps and ridges (like a corrugated iron roof) that are accentuated over time by traffic. Unsurprisingly, corrugations can be uncomfortable to drive over and put unnecessary pressure on your vehicle.

From a speed perspective, there’ll be a ‘sweet spot’ to driving over corrugations, depending on the size and frequency of them. Drive too slowly and you’ll start feeling the vibrations shaking through your car. Drive too fast, and you’ll lose traction and control. Adjust your speed, carefully, and you’ll find that sweet spot where your vehicle’s tyres begin to skip over the corrugations, and the ride becomes more comfortable. As mentioned in the previous section, tyre pressure will be important in navigating corrugation.

Many roads will have tracks - often in the middle of the road - worked into the dirt, and these will be the safest and most comfortable part of the road. On long, straight stretches you should be able to straddle the middle of the road and see any oncoming traffic long before you need to take action. Take extra care, however, when approaching corners or hills, and at all times be prepared to slow down and even pull over to the left when passing cars coming in the opposite direction.

Accelerating and braking should be done smoothly. Avoid any sudden manoeuvres - especially around corners, and try to avoid braking midway around a bend. You should slow down enough to be able to gently accelerate out of a corner and stay in control of the vehicle.

If you do happen to find yourself in a situation where you begin to skid, remain calm and don’t slam on the brakes. Gentle release the accelerator, look in the direction that you want the vehicle to go and steer in that direction with both hands on the steering wheel. A common - and dangerous - mistake when trying to regain control of a skidding vehicle is overcorrection, and it’s vitally important that you avoid jerking the steering wheel and instead steer gently.

There’s a lot to consider, and driving on unsealed roads will require extra focus, and with that comes extra energy. Take regular breaks, and ensure you’ve packed sufficient water and supplies.

The Dusty Dilemma

Thick clouds of dust will be inevitable when driving on dirt and gravel, both from your own vehicle and other cars on the road. It will have a major impact on visibility, and poses extra hazards in the way of loose stones on gravel surfaces.

If you’re travelling behind another car, where possible leave plenty of distance - pull over for a minute or two if you need to - and allow the dust to settle. When passing cars coming in the opposite direction, slow right down to avoid driving through a thick cloud of dust.

It goes without saying that you want to do everything you can to keep that dust out of the interior of your car - you’ll have enough work already in cleaning the exterior. Set your air-conditioning to recirculate, and make sure all vents are closed.

Encountering Wildlife

Driving in remote locations means you’re often sharing the road with wildlife and livestock of all shapes and sizes. Pay constant attention ahead and around the edges of the road, especially around water. If you pass animals on the side of the road, assume that they will instinctively head towards the vehicle, especially at dusk, dawn or in darkness - so slow down and pass safely.

Arrived Safely? Not Done Yet

Once you’ve reached your destination, or simply returned to the relative safety of a sealed road, do a thorough check of your vehicle. Re-inflate your tyres to recommended road pressures, and inspect them for any noticeable signs of wear or damage. Clean your headlights, tail lights and number plate, and check your windscreen for any chips or cracks. If it was a particularly rocky ride, check the underside of the vehicle for any leaks or major dents and damage.

Even for the most experienced and careful drivers, accidents do happen. Visit NRMA Insurance to make sure your car has the right protection.