Are you a 4×4 buddy or more of an AWD dude?
In this article, we help you figure out why 4×4 and AWD aren’t really the same as you think.
Front and Rear Drive Shaft Movement
4x4s are generally composed of an engine, a transmission, and a transfer case. The transfer case can be in two high, four high, and four low. In other words, it gives you an option to run your 4×4 in a manner when the front and rear wheels both get powered by 50%.
And when they all are equally running under the same rate, they also get uniform movement, speed, and direction. Why so? Vehicles of this type have front and rear drive shafts that are both locked in place to execute the same running rate to provide you with better traction on uneven surfaces.
As far as AWDs are concerned, their wheels have a tendency to be driven consistently in a way that they can share similar movement, but they can vary in speed or rate. This is because vehicles of this type are meant to be used on even surfaces for a more stable traction (as opposed to 4x4s).
One important thing you should keep in mind is when you travel on almost smooth surfaces like roads and are bound to make a turn, your wheels are “forced” to move in different paths. With this, you can’t use a 4×4 system’s approach because it automatically locks your wheels in a uniform movement that can make you damage a vital vehicle part.
Center Differential vs Transfer Case
In 4x4s, power started by the engine goes through chosen transfer cases and is relayed to the front and rear differentials.
But what do differentials mean to begin with? Differentials are responsible for making your wheels move at various speed levels. In fact, your engine, transmission and drive shaft are all connected to your vehicle’s differentials via the pinion gear that allows the differentials to spin.
When your vehicle moves in a straight path, differentials execute the same speed but they differ by the time you round a corner or curve.
Differentials come in various types such as:
- Open Differentials – are very easy to maintain but they redirect the engine’s power to wheels that have the least amount of traction.
- Locking Differentials -secure the amount of power between axles and split it equally among the wheels. They ensure that the wheel with highest amount of traction remains stable as in the case when off-roading.
- Break-activated Limited Slip Differentials (LSDs) – are a type of open differentials that put brake on wheels with the least amount of traction. They’re like a defense mechanism if the chance of getting stuck increases.
On the contrary, in AWDs, power from the engine passes through your vehicle’s transmission and goes through the center differentials. From there, power is sent to one of the axles. Unlike 4x4s, AWDs have a second clutch pack that provides additional power to the axles should the need arise.
Overall, the system in AWDs is the one calling the shots in terms of how your vehicle should run which is the exact opposite of 4x4s. Why? The latter lets you choose which wheel axles receive power and how much via the transfer case.
Back in 1920s, AWDs almost make no difference to 4x4s in terms of speed across the wheels hence the term “all-wheel.” However, in today’s generation, AWDs are referred to as the Permanent Multiple Wheel Drive mainly due to being the Jack of All Trades.
Even though their use lies heavily on the road, they provide a balance driving experience across various terrains usually found in the urban areas that makes them known as the all-weather drive type.
Be very careful though, the word permanent here implies that you can’t switch to 2WD even if you badly need to because again, all wheels are meant to be spinning. And because of this, AWDs also eat a huge amount of gas.
There are also other types of AWD; one which consists of two motors like the Tesla Model S and the other which is the Individual-wheel Drive (IWD) where individual torque or speed levels can be adjusted in milliseconds.
With these being said, obviously, 4x4s are those that are truly meant for various kinds of hardcore off-roading, from rock crawling to water crossing.
Part-time and Full-time 4×4
4x4s can be classified into two types; part-time and full-time 4x4s according to the situation you find yourself into because there are more to them than just fancy names for the sake of complexity or sophistication.
When you say part-time 4x4s, these are vehicles that give you the authority to change their systems either into 2WD or 4WD. How do they exactly work?
Part-time 4x4s usually run on two wheels for normal road driving preferences (that affect the rear wheels). However, it can be changed to a combination of four-wheel drive systems for off-road or surfaces where tractions can be challengingly low (this time, affecting rear and front wheels).
How your vehicle responds depends on the drive control or transfer case switch that’s present in your interior.
- H2 high-speed two-wheel drive – is meant for the typical road or pavement that minimizes tire wear as much as possible.
- H4 high-speed four-wheel drive – is meant for uneven and sometimes slippery conditions like those off the road to improve traction or stability.
- L4 low-speed four-wheel drive – is meant for careful ascension to or descension from steep surfaces.
Bear in mind though, never change the transfer case switch’s status from 2WD to 4WD when your vehicle is slipping because it only increases the likelihood of rollover that may lead to fatal accidents.
See to it that your tires stop from spinning before you make the necessary change in the transfer case switch’s status.
On the other hand, when you say full-time 4x4s, these are vehicles in which all the wheels both front and rear are turning. Under this system, the vehicles have a limited-slip differential (LSD) that connects the front and rear differentials as they and the axles help spin the wheels in different rates or speed levels.
But to better understand how it runs your vehicle, your full-time 4×4 system is divided into four categories.
- 4WD high range open – means power can easily pass through the differentials. Other terms for this are unlocked and free.
- 4WD high range locked – means power is split by 50% for the front and rear axles but deprives you the capacity to drive on asphalt or cement as in the case of the usual roads.
- 4WD low range locked – means your wheels are given five miles or less of travel distance per hour.
- 4WD low range unlocked – means you have access to all for categories which makes you extreme off-road ready, provided that your vehicle has a center differential lock switch.
For more details on these four categories, click here.
AWD vs 4×4 Pros and Cons
Now that you know the real nature of 4x4s and AWDs, just because they have peculiarities with each other doesn’t mean you just have to strictly stick with only one of them. You may even be surprised that they have certain pros and cons which may come in handy in the future should you change your mind to try both.
4x4s and AWDs can be really confusing at first but once you dig deeper and try to understand each’s purpose, you’ll know what makes them distinct from each other. However, which of the two is best to use depends greatly on your driving experience and preferences because the situations you may normally find yourself into have a great impact. Comment below if you have anything to add about this topic.