Tips and Tricks: Driving in Dunes

Tips & Tricks: Driving in the Dunes

By Josh Ashcroft

14th June 2021


When I was new to the off-roading scene, a fellow member of the Pacific Coast Rover Club recommended I take a class with 4WD Trainer Bill Burke.

It just so happened he was coming to town for a presentation on his participation the 1991 Tanzania-Burundi Camel Trophy, followed by a three-day training session the Oregon Dunes National Recreation Area near Florence, so I took the opportunity to go to his presentation and join the class.

Not only is the Oregon Dunes National Recreation Area one of the few places in the state where it’s legal to drive in the dunes, it’s also the largest expanse of coastal sand dunes in North America and one of the largest stretches of temperate coastal sand dunes in the world, with some dunes reaching 500 feet (150 m) above sea level. This environment made for a great training area, in part becauase it was a lot more technical than I was expecting. Burke’s class was extreemly helpful and I highly reccomend taking it or one like it. Having someone who is knowledgable and confident in their abilities and knows what the rigs can and can't do and who knows how to extract you should you get stuck relieves a lot of the pressure and anxiety making it a much more enjoyable experience.

If you are new to dune driving, there are a few simple tips and tricks that can make a big difference to keep you safe and preventing a big dig-out, or, in the worst case scenario, a vehicle roll. These tips have helped me in a big way each and every time I head to the dunes.

 


1. Air Down Your Tires

The most important tip you need to remember when driving on sand is air down your tires. I cannot overemphasize the importance and effectiveness of proper tire pressure in the sand. I heard a story about a couple who became stuck in the Australian outback and after being unable to extract the vehicle they, unfortunately, died of exposure. When their vehicle was finally discovered the rescuers were able to drive their vehicle out after simply airing down. So knowing the importance of airing down your tires could literally be the difference between life and death.
 

Decreasing tire pressure distributes the vehicle’s weight over a larger contact patch (the area where your tire connects with the ground), which provides better “floatation” allowing the vehicle to ride or “float” on top of the sand. Airing down decreases the likelihood of spinning the tires and becoming stuck in the sand, which could potentially lead to an extensive recovery. A caveat: if you don’t have beadlocks, we don’t recommend airing down into single digit pressures due to the risk of de-beading the tire. An exception to this would be if you are in a really bad situation - air way down just to drive out, and then air back up immediately.

Sand conditions vary, so understanding how temperature, moisture and time of day can affect psi (pounds per square inch) is important. The Christmas Valley Sand Dunes and the Oregon Dunes Rec Areas, for example, aren’t about 200-miles apart but the sand conditions are very different. At Sand Lake you can get away with much higher tire pressures -- in my own vehicle as much as 20 psi (pounds per square inch), though I usually target more like 15. In Florence, however, 20 psi will leave you digging holes. You really have to air down closer to 12 to 14 psi there, and a few psi can make all the difference in the world.

 

2. Planning Your Route

Part of the fun of dune driving is that dunes are one of the only places where it’s legal to drive “cross-country.” You can pick a path, any path you like. The challenge lies in the fact that heading in the wrong direction can be dangerous. Fortunately, we've included tips below for picking the right path, and techniques for getting yourself moving again should you become stuck.

 

In Dunes a somewhat circiuouts route is often necessary to avoid soft low points and steep cross slops. In this photo we're playing follow the leader where Bill is just taking us through the dunes and by following him we're able to get a better feel for the proper route.


3. The Fall Line

As a beginner, it is important to drive straight up and down the slope, but following the slope doesn't necessarily mean taking a straight line. Some dunes are a series of rolling hills that change direction, so you can’t always pick a straight line to maintain a line that is perpendicular to the slope. The idea of the "fall line" is a useful concept I learned as a snowboard instructor in high school. The fall line is the path an object of your weight and rolling resistance would follow if you were to let it roll down the hill at a controlled speed. This imaginary line is the path that keeps the vehicle pointing straight up or down the slope. It’s an important concept and it translates well to a lot of off-road scenarios.

It’s important to look ahead to where you are trying to go, then find a route that will allow you to reach that destination by following the fall line. When you want to climb or descend, or if you need to traverse, what you're really trying to do is avoid driving across the slope of the dunes. It can be tempting to "ride the bowl", but this is a very advanced skill that if done improperly is very dangerous.

 

An 80 series Toyota finding the fall line.


4. Commit

Once you’ve carefully planned and chosen your path, you need to take the plunge. Your first time driving over the crest of a dune can be really intimidating. Instinct will tell you to hit the brakes. But once you start down a dune there’s no turning back. You have to keep going and, in most scenarios, don’t want to hit the brakes unless it’s an extremely steep slope and the vehicle starts carrying an unsafe amount of speed.

Descending a dune is like surfing a mini-avalanche. Braking simply allows the avalanche to overtake you and as it catches up to you, it catches up to your rear tires first. If you brake too much the sand will force your back tires around, turning the vehicle sideways. At this point there is a high probability of rolling the vehicle. The more you can stick to the fall line, the more stable the vehicle will be, reducing the likelihood of the vehicle rotating and rolling.

On the ascent, you need to maintain momentum without going so fast that you launch off the crest, but if you back out too soon you'll bog down into the sand. If you stop the vehicle while climbing a dune, there is generally no opportunity to re-start. You will have to back down and make another attempt. Backing down a dune can be very dangerous however, so it is extremely important to reverse straight backwards using the principles of the fall line.

 

From the top even small crests like this can be quite intimidating because you usually can't see the bottom let alone the surface you'll be driving on until after you've commited.


5. Just Because You Drove Down It, Doesn't Mean You Can or Should Drive Back Up It

Taking the time to look ahead and plan your exit, especially when you’re coming up to a steep ledge, can prevent hours of recovery. Attempting to winch out of a sand dune bowl is much more difficult than winching up a steep, rocky ledge with good recovery points. Some ledges can be driven down, but your vehcile may not be able to make it back out. As you become more familiar with your vehicle and it's capabilities in the sand it will become second nature but it's always important to look beyond what you are driving down and make sure there is a route to get out.

Ramin and Pete giving a hill climb everything the FJ62 has.


6. Rapid Steering Technique

If you find yourself loosing momentum as you near the top of a climb, rapidly turning the steering wheel back and forth roughly 90 degrees in each direction - as far as you can turn without lifting either hand - can help give you that little bit of extra grip you need to pull you up. This works via several forces working together. First of all, your wheels are no longer pulling straight up the steepest section so they're not fighting gravity quite as hard; secondly, the little bit of forward momentum you have places additional load on the sidewalls allowing the side lugs to help pull you through; and third, it kind of "confuses" the differential sending power back and forth to the wheel that has the least grip. If you move the steering wheel fast enough, you can "stay in front of it" and keep enough resistance to send some power to both wheels. It requires a little practice and discretion, but can be very effective when bogging down right near the crest.


7. Maintaining Forward Momentum - As fast as Possible, as Slow as Necessary

In general, you want to avoid spinning the wheels as much as possible, however, as long as you are moving forward, your vehicle won't dig down to the axles so it's ok to have some wheel-spin as long as you're still making forward progress. If you start to loose forward momentum, more throttle tends to dig the vehicle deeper into the sand. It’s important to recognize this is happening, admit defeat, and lift off the throttle to prevent yourself from becoming really stuck. If you’re on a slope, you should be able back up and take another run with a little more momentum. But if it’s something more complicated, perhaps you’re on flat ground and the sand is just too soft, get out and do a stuck assessment to plan your next course of action.

There is a certain amount of speed that is necessary to top the crest of a dune without overshooting it. Like most things, practice makes progress here. The same thing applies on the descent - you want to keep the vehicle moving at a good clip, but also avoid submarining the front end. Mini dunes can form at the bottom of a larger dune, so there’s often a little ripple or two leading up to it. If you’re going too fast and you hit one hard enough, you can blow your shocks out.

So, you want to go fast, but not too fast… but you never really know what that is until you’ve done it. A training class is a great way to safely build your skills and become familiar with the machinations of your vehicle in a dune environment. When in doubt, go slow and keep adding a little more on successive tries until you find the sweet spot.

 

Driving in the sand can at times require a little wheelspin to maintain momentum.


8. Stuck Assessment

Despite your best efforts, there are times when you will become stuck. At these times it’s important to slow down, take a moment to calm down, get out, walk around the vehicle, and perform a stuck assessment.

Walk around and look. What do you see? Are you stuck because you’ve been spinning your tires and dug yourself so deep that your axles are resting on the ground? Have you hit an obstacle that you couldn’t see from the driver's seat? Did you break something and not realize it? Should you decrease the pressure in your tires? Is the slope simply too steep for your vehicle to climb?

Walking around the vehicle and taking a minute to assess why you are stuck will help inform how to perform a successful recovery. Attempting to move forward without understanding why the vehicle is stuck risks injury to the vehicle, or becoming more seriously trapped.

 

Despite all your efforts, you will at times get stuck.

When stuck. It's good to have friends. A buddy system is always wise but even more so in sand dunes.


9. Technique Before Technology

If your vehicle is equipped with traction control (or if you own a Toyota, crawl control), it is important to understand how this technology works, and where and when to use it. Despite this, it's important to focus on techniques that will work no matter which equipment you have, and more importantly, if your technology fails you need to know how to keep moving. This is especially important because technique forms the foundation of learning to drive-off road.

 


10. Tools to Bring

Sand is the one place where I’ve used a high lift jack for recovery. Bringing the appropriate recovery gear is essential, especially if you’re recreating alone. Below are a few items you should consider bringing while driving on dunes, listed in the order I'd recommend purchasing them.

  • Sand Flag - often required in dune recreation areas but also just good practice
  • Air Down Device
  • Air Compressor
  • Maxtraxx
  • Highlift with Jackbase
  • Kinetic Recovery Rope and Shackles
  • Winch
  • Pull-Pal

 

We are huge fans of MAXTRAX recovery boards. Decreasing tire pressure and utilizing a pair of MAXTRAX can go a long way in the sand. If you aren’t familiar with them, learn how to use MAXTRAX via this video HERE.

 

Driving in the dunes is a completely unique experience requiring its own skill set. It's also a total blast. I hope these tips and tricks, along with additional training, encourages you to get out and explore the sand.