So you’re shopping for a car that will scratch that itch and you’re feeling a bit overwhelmed by the sheer number of options. What kind of engine should you get? Do you need four doors or are you alright with two? What drivetrain should you get?
That last one is what we’re going to talk about today as part of our ongoing series to help you understand the vehicles we love. We’ll look at the pros and cons of each drivetrain layout and help you decide what the best one is for what you want to do with your car.
Instead of just running down a boring list of pros and cons, we’re are going to look at five different metrics of everyday performance and talk about how each layout fits into each category. To start, though, let’s make sure we’re all on the same page and we all understand what all these letters and layouts even are.
Letters and Layouts
There are four main drivetrain options. You have front-wheel drive (FWD), rear-wheel drive (RWD), all-wheel drive (AWD), and four-wheel drive (4WD), which is like AWD, but only sometimes and the differentials are different.
Now, we already have a whole video on AWD versus 4WD, so we don’t really need to get into it here. And chances are if you want a 4×4, you aren’t watching videos on layouts and trying to make a decision because you’re already crawling over rocks in the mountains.
For everyone still here, the “wheel drive” part of the name simply refers to which of the four possible wheels are powered by the engine. The front wheels are the two in front of you, and the rear wheels are behind you, and all the wheels are all around you. It’s a really simple concept, but it can feel a little intimidating. Don’t overthink it and you’ll be absolutely fine.
So, why? Why aren’t all cars AWD or FWD? Let’s start with the first of our categories: complexity.
When we talk about complexity and cars, what we usually mean is cost. How much does it cost to build a simple car like a Toyota Corolla versus how much does it cost to build and maintain a complicated car like a Bugatti Chiron?
This is where FWD wins hands-down because the engine, transmission, and driveshafts are all just one package. That means that manufacturers can build 90% of the car and then just drop in the entire powertrain all at once. Not only does it keep manufacturing simple, but it keeps the entire structure of the car a lot simpler. You don’t need extra transmission braces or rear axles that have to be reinforced, which in turn gives you a lot more room inside the cabin. There aren’t all those drivetrain components taking up space.
Fun fact: the original Mini Cooper was basically the car that started the FWD revolution, followed by the infamous Chrysler K-car, and it was all about making cheap, easy-to-build cars that could fit four people so that everyone could own a car.
Now, I know some of you are waiting to comment “But what about the MR2?” So, this is me acknowledging that, yes, there are some cars like the Fiero and the Lotus Elise and the MR2 that have very similar engines and transmission packaging, but are rear-wheel drive.
However, they’re still a lot more complex because you have to steer the front wheels, so you’re going to need a steering rack, extra suspension, power steering lines, and electronics in the front anyway. That means that, no matter what, any vehicle that drives the rear wheels (whether it’s AWD or RWD) will be more complex than FWD.
And it’s pretty easy to see it when you are looking at the cost of new vehicles. There’s a reason that the most expensive FWD car, which is probably the Civic Type R at nearly $40,000, is still on the lower end of RWD performance cars like the Hellcat or Corvette.
So that leaves AWD which, as you would guess, is the most complicated layout because of the complexity of a rear driveshaft and the complexity of front-engine packaging. Again, this shows up in price, where the AWD option is usually an expensive upgrade, on average adding between 2$2,000 and $3,000 to the cost of the car.
There is one outlier, though, which is an outlier pretty much no matter what you are talking about, whether it’s engine configurations or drivetrains. And that outlier is Subaru, who manages to keep costs way down because they use the same AWD platform on everything. They’ve been doing it for a long time, though, and if you’ve ever worked on a WRX, you know that it’s just a different mindset altogether.
Build cost and complexity aren’t the only reasons to go FWD, though. Another huge reason is efficiency, which is what we’ll talk about next.
A lot of things affect a car’s efficiency, like how far it is from the motor to the drive wheels and how the car behaves while under power. See, to start off with, there’s this thing called parasitic loss of power, which is why a car that makes 400 horsepower at the crank might only make 350 at the wheels.
There’s all this stuff between the engine and the wheels that takes energy to move, and the more stuff there is, the less power makes it to the wheels. On a front-wheel drive car, there’s just a lot less stuff. I mean, you’re talking about a couple of CV shafts that are one foot long versus a 4-foot driveshaft, a differential, and two half-shafts that are over 2 feet each in a RWD car.
However, that’s not the whole story. When a car accelerates, its center of gravity moves back. And the faster you go, the more that matters because, as the center of gravity moves, the front wheels will begin to completely lose their grip on the ground. You’ve all seen videos of drag cars doing wheelies. Just imagine those front wheels spinning as fast as they can, but it won’t do you any good.
What that means is that the faster you go, the more efficient rear-wheel drive becomes, which is why all of the fastest cars on the drag strip are RWD. However, when it comes to miles per gallon and normal driving, front-wheel drive is just more efficient in the real world. The minor differences at low speed concerning traction just do not compare to the lightweight, lower-complexity, FWD designs and the reduced number of rotating parts they can use.
But, we did just mention handling, which is traditionally where RWD is king. But it might be replaced by AWD soon, so let’s talk about that.
We mentioned traction briefly when we talked about the center of gravity moving back when you accelerate, but it goes beyond acceleration. You see, on your car, you’re basically in a constant fight for traction. You need traction to accelerate, otherwise your wheels will just spin and you won’t go anywhere. And while burnouts are sick, it’s not very much fun to just never make it to your destination.
You also need traction to turn because if your front wheels don’t grip the road when you turn the wheel, well, you’ll just fly off the road. On a front-wheel drive car, though, your drive wheels, the ones that need traction to accelerate, and your steering wheels, which need traction to turn, are the same. That’s a lot to expect from a couple of rubber tires, right?
If you separate the drive wheels from the steering wheels, the front wheels can dedicate themselves 100% to turning and the rear wheels can dedicate themselves 100% to going fast. Where that shows up most is when navigating a corner. We’ll a video about understeer versus oversteer, but let us know in the comments if you’d watch it.
The basics are that oversteering is when the front wheels grab the asphalt too hard and the rear end can’t keep up. Most car enthusiasts like oversteer because it leads to drifting or, if you’re unlucky, spinning out and crashing. But it means that you aren’t limited by the amount of steering grip so you can push the car a lot further.
FWD cars, however, usually have understeer, which is the opposite. It’s when you turn as hard as you can, but the car doesn’t have enough grip to actually make the turn so you get pushed to the outside. That means that turning grip is your biggest limiting factor and you have to slow down a lot more so you don’t overtax the tires.
It’s safer, so most cars on the road are set up with oversteer, but it does mean that high-speed cornering is more difficult, which is why most race cars are RWD. Well, that and tradition, because the truth is that because of modern tire compounds and modern aerodynamics, the gap between FWD and RWD is closing rapidly, especially because of the next category: traction.
When we started talking about efficiency, we started talking about traction too. And that conversation continued through handling. As you can probably tell, it’s really important, and it’s where all-wheel drive finally gets to shine. Because when you have all four wheels spinning, you literally have twice the available traction as two-wheel drive.
That means two things. First, you get the worst of both worlds. You get the efficiency loss of RWD and the bad handling of FWD. But the extra grip can overcome a lot of shortcomings too. We talked about oversteer and understeer before, and AWD cars tend to understeer quite a bit. It’s’ even worse than their FWD counterparts because the rear wheels can be pushing the car in the wrong direction.
But, you virtually eliminate the risk of spinning out with an AWD and can launch out of a corner so much harder because of the extra traction. As a result, on modern racetracks, AWD is finding its way to the podium more and more. In fact, some of the fastest racecars on the planet, the LMP1 cars that race the 24 Hours of Le Mans, have almost all made the switch to AWD.
But on the road isn’t actually where AWD shines. To get the most out of an AWD car, you need to head off the road. See, the extra traction means that you can continue to have steering and acceleration even when road conditions wouldn’t allow a two-wheel drive car to move. The front wheels can pull the back out of a slide and the back wheels can push the front out of a rough spot. That’s why AWD dominates rally, something you can actually thank Audi for, and why when you go up north where it snows, it seems like every other car is a Subaru. Snow, as it turns out, is really slippery, and you need all the traction you can get.
If we’re going to rank them, AWD is king of bad conditions, but FWD would come in second because of all that stuff about low-speed efficiency and simplicity. It’s just easier to pull a car along when all the weight is over the drive wheels. And if you’ve ever driven a RWD car in the mud or snow, you know that it just isn’t ideal.
That doesn’t mean it isn’t fun as hell to do, though, which is why we wanted to have one final category, something to get you thinking about what you want out of a car: the fun factor.
There are a lot of ways to enjoy being a car enthusiast. And before we talk about some of the more popular ways to enjoy driving, you have to understand that there’s no wrong way to be an enthusiast. In fact, there are people who are very passionate about doing things “wrong.” For instance, guys who go out and try to build the fastest front-wheel drive dragster possible or, like Ken Block, just drift AWD cars everywhere.
But I think there’s some things that we can all agree on. Drifting is fun; and if you want to drift, you’re probably going to have to stick to rear-wheel drive cars with mad oversteer. And if you want to bomb fire roads, an AWD car is probably a great option. Although if the Gambler 500 is any indication, a rear-wheel drive Crown Victoria is also a wonderful choice.
And if you want to do action movie stuff, it’s rear-wheel drive. We just associate drama and trick driving with rear wheels spinning and oversteer. It’s so ingrained in us that stable, fast driving looks wrong to us. You remember the WRX from Baby Driver? That’s actually modified to be RWD instead of AWD. That’s just how it is, which is why most enthusiasts will gravitate towards rear-wheel drive. It’s just a whole heck of a lot of fun to spin the rear tires and hoon.
I don’t want to just say that RWD is more fun, though. The truth is that every car can be an insane amount of fun. A Mini Cooper being driven fast through tight streets like in The Italian Job? Hella fun. Doing highway pulls in a Lancer? Fun. Taking a Subaru Outback up a mountain to get to your favorite snowboarding spot? Fun. Drifting with lunch trays? You hear people say that front-wheel drive sucks and is no fun but, to me, that just means those people have never gone tray drifting.