CRESTED BUTTE, COLORADO—It doesn’t matter how good your tires are, or your all-wheel-drive system: When the snow’s deeper than your bumpers, you’re going to get stuck.
The snow was much deeper than the bumpers here in Colorado, where it hadn’t stopped falling and blowing for a day. Even the skiers were staying inside, unable to see on the slopes. If they weren’t venturing out, what hope was there for a fleet of Mazda SUVs?
We went out anyway, wipers swiping double-time, headlights bouncing across the glare. All was white, or a little dirtier white where the road was supposed to be. We stayed on the dirtier white path, hoping it boded well. Every now and again, we’d pass a car in the ditch. Better not drive too close to it, then.
We were looking for the Mazda ice track.
Keeping it predictable
For the last couple of months, Mazda’s been flooding a pasture here in the high Rockies to turn it into a bed of ice, all the better for demonstrating its i-ACTIV all-wheel-drive vehicles. There’s a solid base of up to 30 cm of ice so the CX-5 and CX-3 SUVs can prove themselves on as slippery a surface as you’ll ever encounter.
The whole point of the i-ACTIV philosophy is to have a completely invisible traction system that allows every driver to push a car safely over a wider spectrum of driving conditions. It must be fun to drive, without consuming more fuel.
That’s a biggie, because the most predictable AWD systems are those that always drive all four wheels, but they’re doing more work and that makes them thirstier. The more economical AWD systems are those that kick in only when needed. Most of the time, they only drive one pair of wheels, but when those wheels start to slip, they transfer the driving torque through a variable-clutch mechanism to the other pair to seek better grip.
This is called “torque lag,” and it’s the inherent disadvantage of on-demand AWD systems. These days, torque lag is a very brief process with the correct drive being sent to the correct axle almost instantly, but this still wasn’t quick enough for Mazda.
Sensing what’s going on
Every i-ACTIV powertrain takes readings from some 27 different sensors throughout the car, detecting things like throttle pressure; steering pressure compared to the actual angle of a turn; brake fluid pressure; the incline of the road; and even the outside temperature and whether the wipers are on. It does this 200 times a second, so the need for torque to the wheels will be predictive, not reactive.
As well, it takes more than just detected wheel-slip to determine how the power is divided between the axles. The i-ACTIV system allows different ratios for any number of driving conditions, including acceleration and cornering on dry roads; in fact, Mazda says optimum fuel efficiency can often be found with a 40% rear/60% front torque split.
There’s no torque vectoring, though—no division of power side-to-side between the individual wheels, just between the pairs of axles. There is individual braking and the cutting of power to specific wheels through the traction-control system, but not through the drivetrain itself.
Fun on the track
My CX-5 was working overtime on the Mazda ice track. A plow cleared the way of much of the snow, but it was still deep enough to create ruts that tugged the wheels this way and that. The car was fitted with Bridgestone Blizzak winter tires for the best grip possible and I wiggled it between the slalom cones and slid it through the braking zone. All great fun.
In fact, the Mazda is programmed to allow wheel slippage in such conditions, rather than trying to always find maximum grip. It’s a more intuitive way to drive and it’s more fun. It certainly feels more natural.
To better illustrate the car’s capability, I jumped back-and-forth behind the wheels of the CX-5, a Honda CR-V and a Subaru Forester. All have on-demand AWD (the Subaru is on-demand when equipped with a Continuously Variable Transmission), and all fitted with the same Blizzak tires. The three vehicles are in hot competition against each other at dealer lots.
Other drivers weighed the various attributes post-comparison, saying the Honda would bog down in the deeper snow and the Subaru would slide more wildly around the cones. It wasn’t a completely apples-to-apples comparison because the chewed-up snow changed the track a little with each pass, but to be honest, I could find no obvious difference between the three.
Mazda’s CX-5 (right) and a rival Honda CR-V (left) cresting a snowy hill
The Mazda’s advantage was much clearer on a slippery hill, where I took turns to park all three cars on the incline almost at the top and twisted their wheels a full turn to one side. This was supposed to imitate a cottage driveway reaching the road, where you might pause before pulling out into traffic.
The Subaru sent too much power to the front wheels and slipped to one side before pulling away, while the Honda dug in and couldn’t find traction at all. When the ruts grew deeper, it had to be reversed back down. The Mazda, however, pulled away as smoothly and easily as if it was on a dry, flat road. That was an impressive display indeed.
Making the choice
So is the Mazda system the better choice? Under most driving conditions, there’s not much in it. All three SUVs will get you where you want to go, provided you drive carefully and the snow’s not past the axles.
The Forester’s base price of $25,995 makes it considerably cheaper than the AWD CR-V at $30,425 and AWD CX-5 at $30,225, but this isn’t really a fair comparison since the Subaru is not so well-equipped at that price. If you want cargo room and AWD without the bells and whistles, however, the Forester is your most affordable option.
The i-ACTIV system drives the Mazda with no fuss, and it doesn’t come with a fuel consumption penalty. In fact, the new AWD system is 38 kg lighter in the new CX-5 than in the old CX-7, and 26 kg lighter in the new CX-9 than last year’s model. At 60 km/h, the new design allows up to 82 percent less energy loss through the drivetrain than before, which all helps save gas.
So by all means, get behind the wheel of an all-wheel-drive Mazda with winter tires and see what’s the worst the season can throw at you. Chances are you’ll relax when you recognize the SUV really is doing what you expect. And if you can have a little fun at the same time, all the better.