4x44X4 AdviceCar Advice

Should your SUV be all-wheel drive or two-wheel drive?

07 Oct 2019

Robert Pepper 6

FWD vs AWD: So you want to buy an SUV but aren’t sure if it should be a front-wheel drive or all-wheel drive. Here’s what the difference is.

OVER A SMALL wagon or the like, the SUV remains a very attractive option for many reasons, like having some rough-terrain ability and better dirt-road composure. And its higher seating position is both easier to get in and out of (including for babies and kids) with generally better visibility.

So if it’s an SUV you want, you’ll need to consider whether you need your SUV with just two driven wheels or if it should drive all of them. We’ve got a full explanation of the various different drive terms at the end of this article, but for simplicity, let’s run with 2WD (two-wheel drive) for driving two wheels out of the four, and AWD (all-wheel drive) for driving all four.

Note that some heavy-duty offroaders are 2WD onroad, and can only drive all four wheels offroad. We’ll call them 4WDs. Also, many AWDs drive the front wheels with the rears only helping as required. These are called on-demand AWDs.

Do I need a two-wheel drive or all-wheel drive?

For a while, SUVs were exclusively AWD. Now, many are available in both AWD or 2WD, and not just the smaller vehicles oriented towards onroad duties.

This leaves us with many models which can now be bought as a 2WD, and sometimes in the same spec but with slightly more expensive AWD. It’s also the same with many utes:

_{*Fuel use in litres per 100km.}

What does this table tell us?

2WD and FWD vs AWD: The differences

Weight

All-wheel drive and four-wheel drive vehicles aren’t much heavier, though the heavy-duty Ford Ranger and Mitsubishi Triton have a set of crawler gears which accounts for the extra weight.

Purchase price & fuel economy

You pay around 10 percent more for an all-wheel drive SUV and about 15 percent more for a four-wheel drive ute. But the fuel economy – part of the running costs – are hardly any extra, around 5 percent in extra fuel consumption. Fuel consumption is just one part of annual running costs along with insurance, servicing, and registration.

Expect 4WDs to cost a fraction more to service as there’s another differential (set of gears on an axle), and the extra weight would wear the brakes slightly more. However, those differences will be very minor and outweighed by your driving technique. In the case of the SUVs, driving all four wheels at least some of the time would even out tyre wear.

Fuel consumption

Taking the Australian average of 14,000km per year and averaging it across all four vehicles we get 970 litres consumed for the 2WDs, and 1029L for the 4WDs. At $1.50 per litre of fuel, that’s $1454.25 and $1543.50 respectively, and a difference of around $90 per year. That’s $7.50 per month, which isn’t very much. And there are two reasons 4WDs use more fuel – the first is extra weight and the second is the energy required to turn the second set of shafts and cogs to drive the other set of wheels.

If you were to travel half as many kilometres – say around 7000km a year – then the cost would be half as much; $45 per year, or $3.50 per month.

Performance

When accelerating and cornering in dry on-road conditions there will be little difference, but in lower-traction conditions such as dirt roads or on wet roads then the better AWDs have a distinct advantage over FWDs, being able to put power to the ground more effectively. And that goes double for offroading. While we have driven a 2WD SUV offroad, an AWD would be much, much better. Towing is typically better with AWD too, for example, those quick pullaways on a slight angle, and when you’re reversing the trailer on uneven surfaces or low-grip terrain.

What’s better – FWD or AWD?

The 2WD versions of SUVs are much cheaper to buy and slightly cheaper to run. If you only ever want to drive on bitumen roads and occasional dirt roads, they make economic sense. However, if you ever intend to drive in lower-traction conditions such as snow, offroad, or extensive dirt or rough road driving, then you will find AWD a benefit. If you ever intend to drive rougher terrain beyond dirt roads, then consider AWDs only.

Once you’re past the initial purchase price, the AWD/4WD version of the vehicle costs little more to run. You also need to consider resale, as someone looking for a 2WD may take an AWD, but someone set on an AWD won’t want a 2WD.

What the Drivetrain jargon means

2WD – two-wheel drive. Typically means a four-wheeled vehicle with two wheels driving, but doesn’t specify whether the driving wheels are front or rear.

FWD – front-wheel drive. All FWDs are 2WD. Note: Does not mean four-wheel drive.

RWD – rear-wheel drive. All RWDs are 2WD.

4X2 – Four wheels, two driving. Another way of saying 2WD.

4X4 – Four wheels, all driven. Implies offroad use. Some offroad vehicles are 4X2 onroad, and 4X4 offroad.

AWD – all-wheel drive. Means all wheels driven and implies on-road use as opposed to rough-terrain use.

On-demand AWD – drives mostly in 2WD for reasons of fuel efficiency but moves to AWD when computers decide more traction is needed.

4WD – four-wheel drive. Implies offroad capability.

The above definitions are not strictly accurate because terms like 2WD and AWD assume the vehicle in question has four wheels; it is possible to have 6 wheels and 2 wheels driven, and that’s 2WD – and also 6X2.

If you’d like to join in the discussion on FWD vs AWD, comment below or get involved on our Facebook page.