This or that: 2WD, AWD or 4WD?

You've picked the car, body style, trim, engine and transmission. Maybe you've even chosen the colour. But your deliberations might not necessarily be finished yet. Depending on the car and/or your personal requirements, you might also have to ponder which wheels you want the engine to drive.

At its core, this is the choice, but the reality is more complicated. Within the two-wheel-drive (2WD) spectrum are front-wheel-drive (FWD) and rear-wheel-drive (RWD), each with their own strengths and weaknesses.

Within the four-wheel-drive (4WD) division lies all-wheel-drive (AWD), which logic tells you is the same thing but – owing to car-makers needing to find ways to differentiate products in an increasingly complex market – actually isn't.

Whichever drive setup will serve you best comes down to a complex interplay of personal requirements, driving style, driving environment and budget.

For a long time, most cars drove only the rear wheels and the traditional setup still stacks up. Because each set of wheels has its own job to do (i.e. steer and drive respectively) and the weight of their engine/drivetrain combo can be distributed evenly through the chassis, RWDs tend to have what’s called a ‘natural' handling balance. Because weight during acceleration shifts to the rear, they're great at putting their power to the ground. Sling a trailer, boat or caravan on the back and that advantage is maintained.

Having the engine/driveline combo under the bonnet rather than spanning the vehicle makes an FWD simpler and cheaper to manufacture than an equivalent RWD. It's why most affordable mainstream cars are FWD, whereas luxury, sports, and other cars where the qualitative experience counts will often be RWD or AWD. This concentrated mechanical layout also means FWDs tend to have the best cabin/boot packaging of all layouts.

They aren't without their driving attractions either. The compact FWD mechanical layout brings weight and efficiency advantages; they tend to have better traction than an RWD in really slippery, icy, or snowy driving because their weight is concentrated over the driving/steering wheels.

The way an FWD handles emergency maneuvers is also safer for most drivers. They tend to push their nose wide, which can be contained simply by lifting off the throttle – a natural response in this situation – where RWDs tend to slide their tail out, which requires an expert hand to reign in. Modern driver aids have basically eliminated this advantage but this physical characteristic remains.

Technically, every AWD is a 4WD but the former generally stands for a passenger car – a category that includes the ubiquitous SUV – that drives all four wheels. So why would you want that? Well, the big advantage is better traction than either 2WD setup, which means less wheel spin and safer, more secure progress in slippery, uncertain conditions, a benefit that carries over to towing.

The additional drivetrain components needed to send drive to all four wheels, however, mean AWDs do cost more than 2WD equivalents. Additional weight means they can be marginally slower (not electric all-paw options, however, which often add more motors to gain drive to all wheels) and use more fuel.

Just like an AWD, a 4WD drives all four wheels but '4WD' now typically means a heavy-duty off-road vehicle rather than a passenger car that merely drives all four wheels. It means you'll be getting a properly capable off-roader with a robust build, generous ground clearance, and low-range gearing.

These other assets often mean the advantages of driving on all four wheels are maximised, a real asset if you intend to properly venture off the beaten track or tow heavy loads in challenging conditions. But because they're built to take punishment they're generally heavier than even an AWD, meaning even bigger performance, economy, and handling compromises.

^Disclaimer

^{Viva Energy Australia Pty Ltd (“Viva Energy”) has compiled the above article for your general information and to use as a general reference. Whilst all reasonable care has been taken by Viva Energy in compiling this article, Viva Energy does not warrant or represent that the information in the article is free from errors or omissions or is suitable for your intended use.}