Rain, sleet, hail, snow. What do they all have in common? They can really screw up a day of driving! Especially if you’re expecting to get to your girlfriend’s house in some little wrong-wheel drive jalopy with a blizzard howling outside!
Alright, so your front- or rear-wheel drive isn’t designed to tackle that sort of turbulence, then what is?How about a badass brawler with 4-wheel drive? And what about SUVs and sports cars with all-wheel drive? Will they get you there? What the hell’s the difference between 4-wheel-drive and all-wheel drive anyway?
Well, if you don’t know you’d better stick around, because in this article we’re going to tell you everything you need to know about 4-wheel drive versus all-wheel drive!
What’s the Difference?
So, you want a car that’s going to handle well in hairy conditions. Of course, you’re going to need a ride that’s pushing power down to all 4 wheels. Well, we here at ideal have some good news for you, because you’ve got, not one, but two choices: all-wheel drive or 4-wheel drive. And if you’re a novice car buyer, you might not know the difference!
Both are good in their own right. Both have their pros and cons. Sure, they both power all 4 wheels, but which one you choose could be the difference between gliding comfortably down a snowy road and ending up in a ditch.
All-Wheel Drive
So, let’s start out with the more common: all-wheel drive. Why is it more popular than 4-wheel drive?Well, it’s because carmakers have optimized all-wheel drive for on-road use. Is it better on the road than 4-wheel drive? You bet. All-wheel drive has the ability to send torque to all 4 tires simultaneously hile modulating the amount of torque between the inside and outside wheel to maximize grip. That’s the name of the game: grip, the arch nemesis of its evil twin slip!
More grip means better cornering speed and less slippage on each wheel when driving in treacherous weather. So, how does all-wheel drive actually get that grip? It uses fancy differentials to distribute power to whatever wheel that needs it most based on slip, or even take power away from a wheel if necessary.
The Subaru WRX STI, for instance, uses an additional center differential, which acts just like the differentials in each axle. But instead of splitting power between left and right, it’s split front and back. And with an STI you can choose your front-to-rear torque split, so if you want it to be rear-wheel drive-biased, just scroll that thang back and feel the driving dynamics change completely.
But not every all-wheel drive has full-time all-wheel drive or the three-differential setup like the STI. The other type of all wheel drive system is called an automatic all-wheel drive system. Ditching the center differential, automatic all-wheel drive uses a transaxle to power one set of wheels while a driveshaft moves power to a differential on the opposing axle.
This setup has some serious pros and cons, since the transaxle-powered wheels get most of the power, which means it only gets the benefits of all-wheel drive in low traction systems. The full-time all-wheel drive, on the other hand, can put equal power to all 4 wheels. Another good thing about automatic all-wheel drive is that it takes up less space and allows the car to run more efficiently when running exclusively through its transaxle.
So, if you’re confused as all hell by what I just said, don’t worry. The point is that even among only all-wheel drive systems, there are some major differences in bad weather performance and miles per gallon.
4-Wheel Drive
But what about 4-wheel drive? I bet you’re imagining a lifted pickup running through the mud, or maybe a Hummer crawling through the desert. Nice to see people using lifted trucks and Hummers for what they were actually intended. And, no, I don’t mean dominating three parking spaces at once.
4-wheel drive vehicles are designed to take on the most challenging terrains on Earth. Well, that is, if you give yourself enough ground clearance and some proper tires. But did you know that cars or trucks with 4-wheel drive generally don’t use that 4-wheel drive all the time? Yeah, no matter how many 4×4 badges manufacturers throw at you, your bro-dozer probably isn’t driving all of its wheels all the time.
So, unlike all-wheel drive cars that constantly power all 4 wheels, most 4-wheel drive systems are turned on by turning a knob, pushing a button, or shifting into it. Maybe if you’re Doctor Strange, you can do it with your mind.
Why isn’t 4-wheel drive powering all 4 wheels all the time? Are you being deceived by your Jeep? Well, it’s basically because when 4-wheel drive is selected, it locks the front and rear differentials together, making both wheels on each axle turn at the same speed.
What if you’re driving on paved roads? Normally a car’s wheels rotate at different speeds when you’re turning a corner, but when a 4-wheel drive system locks the front and rear driveshafts together, you get all 4 wheels going the same speed. So, if you were to try taking a sharp corner with 4-wheel drive, your driveline is going to bind up, and you’ll both feel and hear a mean shake and rattle. It’s kind of like a massage chair, if massage chairs were terrifying and life-threatening. And if that turn is too sharp, your front tires might hop and loose grip of the asphalt, and that, to put it lightly, is just not something you want.
So, why are 4-wheel drives even sold? It sounds like they’re just downright worse than all-wheel drive, right? But wait, do all-wheel drives still beat out 4-wheel-drives on loose surfaces like snow or sand or mud? Well, no, not exactly.
In 4-wheel drive, the locked up axles actually provide more grip than all-wheel drive. But won’t the front wheels just hop around like the Energizer Bunny off a disco biscuit? Nope. Instead of hopping around, the front tires are actually able to lock together with the rear tires, so they move around more freely on not-so-solid surfaces.
While you might just confuse your fancy all-wheel drive differentials in snow, sand, or mud, 4-wheel drive will just lock together and trudge right along. That’s why you see 4-wheel drives in off-roading monsters like the Jeep Grand Cherokee Trailhawk, or the RAM 1500 Rebel.
However, there are capable front-wheel or rear-wheel drives for the avid off-roader, like a MK7 Golf GTI, or a Porsche 911 Safari, because traction doesn’t just have to do with the wheels that they power. Cars with better-suited tires and less-powered wheels can be just as capable, or maybe even more so, than ones with ultra-powered wheels trash-heap tires.
Weight a Minute
I’ll say it again. Grip is the name of the game, and another factor that weighs into grip is, well, weight. Having a lighter car is better in certain situations. That’s why Subarus are well respected for their off-road prowess. Whether they’re slinging mud or spitting out sand, their light builds compared to other 4-wheel or all-wheel drive models make them an absolute off-road weapon.
A brand new Subaru WRX tips the scale at 3,300 pounds, whereas a two-door Jeep Wrangler is 700 pounds more! It’s not like the Wrangler needs to go on Jenny Craig or anything, that’s a light 4-wheel drive, but Subarus are just that much lighter.
So, while it’s important to know the differences between 4-wheel and all-wheel drive, it’s also important to understand that it’s not everything.
Final Thoughts
So, the answer to the question, “What’s the difference between 4 wheel drive and all wheel drive?” just isn’t that simple, as I’m sure this article showed you. If I were you, I would stick with all-wheel drive for on-road use and maybe the occasional off-road stint. But if the Baja 1000 is your commute, then it’s got to be 4-wheel-drive or die, baby!
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