Off-Roading 101: The Importance of Traction Control—Tires, Lockers, and Suspension
Having optimal traction when venturing off-road is critical. Between steep climbs, varied terrain, and harsh conditions, ensuring maximum traction is paramount for those who seek to travel the trails. So how do you get maximum traction control when off-road?
Having good tires is the place to start. Adding drive train parts, such as an ARB Air Locker, and a proper suspension system, can up your 4WD vehicle’s game by orders of magnitude, giving you the ability to make the most of your adventure.
Traction is simply the resistance between your vehicle’s tires and the ground which offers you control of the vehicle. And when you’re off-road, you want as much traction as you can get. Here are some ways to get tip-top traction when off-roading.
Have the Right Tires
The first rule of traction is to not only get good tires, but also the right tires for the terrain and conditions you’ll be in.
A good all-terrain tire can offer a great mix of on- and off-road capabilities. All-terrains provide better traction in dirt, gravel, rocks, and sometimes even snow (especially when three-peak mountain snowflake rated) when compared to highway tires. While slightly noisier than highway rubber, they’re usually more durable, and provide a big upgrade when you leave the tarmac. Note: All-terrain tires don’t usually excel in mud.
If you’re planning to be in muddy environments, opting for a mud-terrain tire is a solid choice. The unique tread patterns and larger tire lugs provide opportunities to clean out the mud, preventing them from caking up and losing traction. They can also be great on the rocks. The downside to mud-terrain tires: They’re louder than all-terrain tires on the pavement, and often don’t perform as well as all-terrains in snow or ice.
Some tire brands offer a hybrid of all-terrain and mud-terrain tires, for a mix of the two tires.
Adjust Your Air Pressure
When you venture off road, you should adjust your tires’ air pressure to ensure maximum traction. Lowering the pressure will help tires flatten out, giving them a wider footprint, and letting them wrap around obstacles, such as rocks, stumps, or ledges for better grip.
How low can you go? It depends. If you’re running wheels without bead locks (which hold a tire’s edge or “bead” onto the wheel), a general rule is to stay above 10–12 PSI. Too love of a pressure can result in the tire slipping off the wheel’s rim. However, if you have bead lock wheels, you can essentially drop the tires to almost no pressure.
Consider what kind of terrain you’ll be in. Soft sand and snow will generally require a lower tire pressure than running dirt roads. If you’re rock crawling, you may want to go lower than if you’re on a moderate trail. Experiment with different pressures until you find one that works for your vehicle and terrain.
Adding Locking Differentials
From the factory, most 4WDs have open differentials, allowing power to be shifted from one side of an axle to another when driving. You’ll want this when going around a corner on pavement because the left and right wheels need to turn at different speeds. Having your differentials open on pavement prevents the driveline from binding. However, if a wheel loses traction, an open differential sends power to the wheel that slips—not ideal when off-roading.
For maximum off-road traction, having a differential that locks the axles 50% to the left and 50% to the right (aka a “locker”) is ideal, especially when traversing obstacles where one wheel may leave the ground. This way, the wheel in contact with the surface will still get power.
ARB offers drive train parts what called air lockers. Air lockers use compressed air to engage or “lock” the differential when desired. An air locker is a type of selectable differential, meaning you can lock and unlock it with the flip of a switch. Other types of lockers include electronic lockers, which are actuated by solenoids, mechanical lockers, manual lockers, ands spools.
Trusted by weekend wheelers and professional racers alike, ARB Air Lockers give you the extra traction you’ll need when you tackle any trail.
Drive Train Parts: How a Locker Works
A differential is one of several power train parts that affect a vehicle’s drivability and can add traction. A locking differential, such as an ARB Air Locker, replaces a vehicle’s original differential. Because the air locker can be engaged and disengaged, these drivetrain components provide the same drivability as an open, OEM non-locked differential, but can be engaged when the trail get tough.
Here’s how an ARB Air Locker uses compressed air to lock the differential:
- For an ARB Air Locker, you’ll need an on-board air compressor with a minimum of 70 PSI and maximum of 150 PSI to engage the locker.
- An air line is plumbed from the compressor to the differential.
- There’s an actuating solenoid controlling the airflow to the differential, which is activated when you flip the compressor’s switch on.
- Once running, a solenoid opens a valve, and air is sent into the locker’s air chamber.
- The compressed air presses on a piston seal and pushes up on the locking gear, locking the side gear into place which locks the rest of the gears. This increases axle driveline strength by 40% due to the ARB Air Locker’s strength.
- Your axle is now locked, and the axles will turn at equal speed, providing maximum traction.
To unlock, simply flip off the switch and the system depressurizes. A return spring pushes the locking gear back into place, and you go back to having an open, unlocked differential.
ARB Air Lockers: It’s What’s Inside That Counts
There are many vehicle and drive train parts which make your rig work, but all the power ends up going through the differentials. If you compare an OEM open differential to an ARB Air Locker, you’ll notice some differences.
The ARB Air Locker is more robust than most OEM differentials with more metal and strength. ARB Air Lockers have four forged spider gears whereas many OEM diffs only have two. This gives more support to the differential’s side gears under load. Their added strength and ability to be either open or locked lets them offer exceptional off-road performance and increased traction.
Air Locker Installation
Installing an air locker isn’t for the novice mechanic and should be done by a professional installer, or someone who has the right knowledge about setting up a vehicle’s gears.
Before installing the locker itself, the air compressor should be placed in a good location, have the right length of air line, and correct plumbing to the axle housing. The air compressor’s switch should also generally be mounted somewhere easily accessible by the driver.
An ARB Air Locker can be installed in the front axle, rear axle, or both, depending on the vehicle. Of course, a rig with locking front and rear diffs will offer the greatest traction benefits when the trail gets tough.
When to Use a Locker
When do you want to engage your locker? The answer: Whenever you encounter terrain that’s uneven and could cause wheelspin and a loss of traction. This could be a jagged hill climb, a rocky section of trail, or any other time one wheel might lose its ability to grip. Simply flip the on switch, and the differential will lock. When done, flick the switch to the disengage setting, and carry on down the trail.
It's good practice to disengage your air locker when you don’t need it. This keeps pressure off all parts of the system and makes it easier to make tight turns, especially on high-traction surfaces like asphalt.
Suspension: Keeping Tires on the Ground
We’ve talked about tires, vehicle transmission and drive train parts (in the form of a locking differential), but suspension can play a role in traction, too.
A suspension system designed for the rigors of off-road use will help to keep your tires firmly planted on the ground, giving your vehicle the best chance at maximizing traction.
Suspension systems, such as those from Old Man Emu, are intended for the demands of off-road use. This includes special shock/strut tuning, custom spring rates, and durable components made specifically for your vehicle make and model. Whether you’re driving the desert, running the Rubicon, or traversing twin track, a suspension system that works with your specific vehicle will help to ensure your rubber stays as firmly planted on the earth’s surface as possible.
Traction Is King
The combination of the right rubber, locking differentials, and a proper suspension system will give you the best chances of making it through your next adventure without getting stuck. It can also add more comfort, more capability, and more fun to your next adventure.
