Crossovers aren’t normally equipped to go off the beaten track. With no low-range transfer case or locking differentials, the most rugged thing they’ll end up doing is climb up the mall parking lot ramp. However, as buyers look for choices that give them an increased level of capability (it’s a security blanket more than anything), carmakers can’t ignore engineering crossovers with an increased level of skill for dirt and mud.
Various carmakers have come up with their own solution to increase a crossover’s unpaved terrain ability from Subaru’s X-Mode to Ford’s Terrain Management System. For Mazda, they’ve eschewed coming up with their own dedicated off-road mode simply because they thought their predictive i-Activ AWD was so good, it didn’t need it. True enough, it can send power between the front and rear wheels in a fraction of second using data sampled from 27 sensors computed at 200 times a second.
But on rough terrain, this may not be enough. Imagine a wobbly restaurant table with a piece of paper wedged under its short leg to keep it from rocking. If you take that piece of paper out, the air under that table leg is like the air under your tire in that diagonal twist. Now, what happens when the table rocks, and that leg comes down? The opposite leg goes up. The same thing happens in a diagonal twist. If one tire comes off the ground, the opposite tire also comes off the ground, or at least gets very light.
So even if the torque coupling that drives power to the axles forces the front and rear tires go to the same speed, if one front tire and one rear tire are in the air, those airborne tires can still spin freely. To stop them, Mazda uses the traction control system to apply the brakes to the spinning tires, forcing torque over to the tires that are on the ground.
In any other situation, the traction control system must apply the brakes as smoothly as possible so there’s no interruption in the driver’s control of the car. But in situations where an abrupt power shift is necessary—like this diagonal twist off-road situation—Mazda’s Off-Road Traction Assist comes in handy.
Replacing the “TCS Off” button in the CX-30, Off-Road Traction Assist stops reducing the engine torque and increases the brake force on the wheels without traction. This transfers power to the wheels still on the ground to help allow the vehicle to regain traction and continue driving. Think of it as having locking differentials, without the heavy and inefficient hardware.
This trick technology does lend a bit more off-road credence to the CX-30, but be warned: it’s still far from perfect. For instance, it doesn’t give Mazda’s SUVs any sort of hill descent control—something that’s found in other crossovers with a dedicated off-road mode. Moreover, flipping through the owner’s manual reveals that Off-Road Traction Assist isn’t designed for prolonged use. It can be used in muddy, sandy, uneven, or deep-snowy roads, but even then, there’s a warning: “Do not drive the vehicle off-road;” safe to say, even Mazda says heavy trails are best left for true SUVs. What’s the primary purpose of Off-Road Traction Assist then? It’s simply to free tires that are stuck.
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