Corrugations can be terrible for both the passenger's comfort and the vehicle. Nuts, bolts and screws, pipes etc can easily rattle loose in a short period of time. Many outback roads in Australia
are heavily corrugated but there are two things that will ease the comfort factor.
To ease the comfort of the ride and to aid in traction on particularly bad corrugations such as the Gibb River Road
or the Development Track to Cape York
it is best to reduce tyre pressures about 4 to 6 psi lower than what you run on the bitumen. Very rough and stony country such as the Birdsville Track
can handle even softer tyre pressures. This may not seem to make sense at first, but if you consider that your tyre is just like a balloon being bounced over sharp objects then you can see how the higher pressure would make it more prone to "popping".
It is also far preferable to keep speed constant and if you feel confident to handle your vehicle in prevailing conditions then try to aim around 85km/hr. You will find that you can "ride" over the worst of the corrugations at this pace. Any faster can be dangerous, slower and the corrugations may shake you and your vehicle to pieces. There is no perfect tyre or tyre pressure and a combination of luck, speed and driver skill will be the secret to minimising flat tyres and maximising tyre wear.
One of the main reasons you would consider altering the suspension
on your 4WD vehicle is improved ride. For many people the standard vehicle suspension
is just not suitable for the heavy load put upon it when fully geared up for touring - fuel, water and supplies can add up to about a tonne and that's usually directly over the rear suspension
Of course, if you've already bottomed out your suspension
with the load when the vehicle is stationary, imagine what's going to happened when you hit the corrugations! Adding a few inches of suspension
will not only feel more comfortable to the driver and passengers, but it will improve general handling of the vehicle which is a valid safety consideration. For a more detailed discussion on the need for suspension
adjustment, see our Suspension