Expert tips and techniques to improve your dirt road driving skills.
By Allan Whiting
Dirt roads driving tips
All the best bush locations are at the end of dirt roads. Getting there and back safely requires driving techniques that are different from those you need for plodding along the bitumen
Road trip cruising on bitumen
You've left the Big Smoke behind, the bitumen stretches out to the horizon, the cruise control is on, the stereo is playing in the background. You get into the habit of surveying the big picture. Bliss!
However, in a holiday-loaded vehicle, don't tear along at speeds that are too high for the road and load conditions. Experienced bush drivers cruise on good bitumen at around the 100km/h mark and enjoy a relaxed drive. This speed allows anticipation of road and traffic conditions and doesn't build up momentum that may be impossible to control if conditions change suddenly.
The two-hour rule is absolute: a driver rest every two hours and preferably a driver change. This break lets everyone stretch their legs.
Then, after a couple of days, you're in the real scrub. The road turns to gravel. Hopefully, you've planned for this eventuality and you've fitted the correct dirt road rubber.
Tyres for gravel roads
The standard tyres fitted to most vehicles these days are totally unsuited to gravel roads, especially those roads with stones larger than golf-ball size. The lower the profile of your tyres, the less capable they'll be on gravel. Assuming all is well with your tyre specifications you may be able to lower pressures by 10-15 percent, to allow the tyres to flex as they pass over rough surfaces. Don't lower pressures in hot tyres: wait until they're cool.
Driving on loose gravel and dirt roads
At this point your concentration needs to change to the 'detail picture': no cruise control, speed reduced to no more than 80km/h, and your focus tightened up to observe the surface and the roadsides that are only a few hundred metres ahead.
Driving on loose gravel and dirt roads is like driving on ice: easy does it. Anticipate speed changes well ahead and wash off speed when approaching corners or hazards so you don't have to brake heavily.
When a loaded vehicle gets out of shape on slippery or loose gravel it takes an experienced hand to get it back in line. Too often the result is a roll-over.
Bush roads are much less predictable
We've never driven on a gravel road that has a constant surface: every few kilometres there's a change in surface, caused by the clay top breaking up into bulldust holes, water erosion digging channels across the track, or just a lack of maintenance. Many bush roads are the responsibility of local councils, who simply don't have the funds to grade roads constantly.
A change of surface is obvious, if you have your eyes on the road ahead, but even then, you can have a nasty surprise, like a sharp piece of stone sticking out of the substrate, or a piece of debris that's fallen off a vehicle.
Driving over corrugations
There are many theories about how to drive over corrugations. The trick is to find the 'sweet spot' where the tyres are skipping across the tops of the corrugations. On most Australian gravel roads that sweet spot is around 80km/h for cars and 4WDs. There are likely to be other smooth-ride speeds, but usually they're too slow or way too fast.
Wildlife on roads
Wildlife is a constant hazard on gravel roads, particularly those roads that aren't heavily trafficked. In daylight the most likely road-wanderers are cattle and emus, and both species' behaviour is totally unpredictable: you think they're strolling away, when there's a sudden mind-change and they're back in front of you. Slow down to walking speed when approaching animals.
Kangaroos come out at dusk, so avoid driving into the setting sun or at dusk. We're usually camped by then. Dodging 'roos in the dust with the sun in your eyes, or during the half-blind conditions that prevail at that time is no fun for anyone. Smack a big 'roo hard enough and your holiday is over. If you must drive at night in 'roo country and you see evidence of carcasses on the roadside, keep your speed down. It's possible to navigate your way through 'roo packs at 60 km/h, but if you insist on running at 100 km/h you'll hit one for sure.
Sharing the road with trucks and other vehicles
If you see an approaching truck, pull over and stop. Road trains produce a mini dust storm, so wait until the cloud has passed by before heading off again.
For approaching vehicles, slow down to walking pace as they pass and you won't get stone chipped.
Overtaking is an extreme hazard, because dust obscures your vision and flying stones threaten your windscreen and radiator. Don't do it unless you can see well ahead and can drive clear of the stone shower. If you want to overtake a truck try calling him on UHF 40.
Smart planning for a pleasant trip
Plan your trip so you're not under pressure to be somewhere every night. The starting point for a successful bush trip is planning that doesn't force you to drive big distances every day. You may be able to count on doing 700km each day on bush bitumen, but poor quality gravel may drop that daily distance to 400km or less.