BUYERS GUIDE
SOFT-ROADERS AREN'T REAL 4WDS
Don't expect bullet-proof attributes from car-based all-wheel-drive vehicles.

Don’t take any notice of TV ads showing soft-roaders tearing through beach-front salt water. Do it and you're certain to void your warranty and you could be on the path to an expensive recovery or total loss.

softroader limitsThe typical soft-roader has no low-range gearing, car-height ground clearance, little underbody protection, passenger-car tyres and lightly-built suspension components.

In the home countries in which these machines are designed and built that formula works very well in fulfilling buyer needs for 'traction vehicles'.

Traction vehicles have desirable passenger car or people-mover attributes, with improved tractive ability. In almost all cases that tractive ability is used for better mobility in wintry conditions - ice and snow - and on smooth but muddy farm access roads.

In Australia the softroader buyer enjoys the same abilities, but is also likely to try fire trail exploring and beach driving.

Almost all softroaders were never designed with even mild rock-hopping in mind and driving on a beach is something Europeans, Japanese and North Americans only dream about.

softroader limitsPushing softroaders into many typical Australian pursuits stresses them beyond their design limits and results in mechanical trouble.

Fire trail driving isn't possible in the Northern Hemisphere. European and Japanese rural areas are built out or locked up and dirt roads are few and far between. The distinction in the US of A between a dirt track and a 4WD trail is quite marked, so soft-roaders generally know their place.

In Australia it's tempting for soft-roader 4WD owners to drive on fire trails, because they're designated ‘4WD only’. However, that designation is made in the original - not the modern - sense. Many track descriptions now indicate the need for high ground clearance as well as 4WD.

It's true that a well-driven softroader can negotiate many fire trails and off-road tracks, but the margin for error is small.

The across-track drainage trenches that reduce track erosion often have lips that can hang-up a low-ground-clearance vehicle, or damage its driveline.

softroader limitsRock shelves that are easily cleared by 'real’ 4WDs are a challenge for softroaders, in terms of gearing as well as ground clearance.

Because softroaders lack the deep reduction gearing that allows an engine to spin up to peak torque at very low track speeds they need to approach obstacles at higher speed. This approach means impact with an obstacle at higher than desirable speed, reducing the chances of 'walking' over it with all four wheels on the ground and increasing the likelihood of suspension or body damage.

Most on-demand soft-roader 4WD systems aren't designed to work in rocky trail conditions: their brief is rear-axle-drive brought on by wheelspin at the front, as happens in icy or slippery conditions. So, by the time the rear and starts to help with traction the front end has already lost traction.

softroader limitsA beach is viewed by most people as a 'soft' destination, but it's not.

When we want to check the strength of a 4WD's driveline or the capability of its cooling system we run it around on soft beach sand for a few hours. Driving on sand means there’s a constant little hill in front of each tyre and some slip under each contact patch, and that makes the vehicle work hard.

Driving on a beach is likely to result in a bogging and softroaders have limited ability to extricate themselves. On-demand soft-roader 4WD systems can't react quickly enough to traction loss at the front end and so the front tyres start to dig in: fatal in soft sand.

Even with full-time or selectable full-time soft-roader 4WD systems, manual versions lack the low-range gearing to get started again and autos make up for their poor gearing with torque converter slip that overheats the transmission fluid very rapidly.

softroader limitsWhat soft-roaders could you consider for trail driving and limited off-road work?

Our testing has shown that the most capable soft-roader by far is the new V6-petrol Jeep Cherokee Trailhawk or its turbo-diesel Limited equivalent. Both these vehicles have nine-speed automatic main transmissions and low-range transfer cases.

We tested his pair against Jeep Grand Cherokee and Wrangler ‘real’ 4WDs in steep Victorian High Country conditions and both vehicles went where the more bush-oriented vehicles could go.

softroader limitsNext in ranking order are Land Rover’s Discovery Sport and its predecessor, the Freelander 2. They lack low-range gearing but a torquey diesel engine makes up for a lot of that gearing deficiency.

We tested them against the new Range Rover Sport, with its low-range gearing and height-variable air suspension and the Disco Sport and Freelander 2 went where the Sport could – with less panel damage risk.

Next in the softroader rankings is the Skoda Yeti, mainly because it can be had with optional fibreglass protection panels on its underside. These give some protection to the underbody and stop sticks from jamming around brackets and pipes.

softroader limitsWe tested a couple of them around Alice Springs, including the treacherous Boggy Hole track and found the little wagon quite off-road capable.

Japanese and Korean soft-roaders are beautifully made and have superior warranties, but they’re not as off-road friendly as the 2015 Cherokee and the European models we’ve mentioned.

That said, don’t even think about going off road in any soft-roader that doesn’t have a proper spare wheel and tyre that match the four rolling ones. Volvos, BMWs and Mercedes-Benz don’t have proper spares.


Bush tyres required

Along with gearing and ground clearance issues, tyres are an important consideration.

Soft-roaders leave the factory on tyres that aren’t suitable for bush work and you need tougher rubber if you’re going even mildly bush.

It’s important that you buy a soft-roader with wheels that can mount light-truck-strength tyres. That means 19-inch wheels and 20s are definitely out of consideration.

Light truck tyres have heavier-built casings than passenger-car tyres, making them much more resistant to punctures. There are several LT tyre fitments for 18s and many more for 17s.

 




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