Vehicles come equipped with, typically, at least two different drive configurations, four-wheel (4WD) and two-wheel (2WD). The reason for this is to ensure that your vehicle is maximizing its capabilities in any given situation. While some recent models come equipped with an automated system that handles the 4WD option for you, it also may fall on the driver to know when and where to do make the change.
So, when is it time to use your 4WD?
The most common situations that benefit from 4WD are; when driving on difficult terrain, i.e. off-roading, in snow or ice, when towing heavy loads, and, of course, when your car gets stuck. 2WD will be more than capable in your average situation, such as driving on the highway or on well-paved, or even bumpy, roads. It’s when the roads are no longer average, such as after heavy snowfall, on a steep slope, or poorly packed gravel, that 2WD may not cut it.
When it comes time to determine what to use, you will need to examine the situation itself.
When Should You Use 4WD?
Deciding when to use 4WD might seem straightforward, and there are certainly the obvious situations that everyone knows. However, when the panic hits, or in less common scenarios, sometimes the best choice is unclear.
2WD vs. 4WD
Both 4WD and 2WD offer performance advantages specific to the situation at hand and knowing when to use them can significantly enhance your vehicle’s performance.
- The engine power is sent to only two wheels.
- Power can be sent to either the front or back wheels, depending on your vehicle and its drivetrain.
- Both front-wheel and rear-wheel drive are great for fuel economy.
- Both front-wheel and rear-wheel drive are best for dry, smooth, or lightly bumpy roads.
- Front-wheel drive enhances traction and stability; this is most common in vehicles such as sedans.
- Front-wheel drive handles rainy weather and the resulting slippery roads extremely well.
- Rear-wheel drive optimizes acceleration; this is most common with sport or luxury vehicles.
- Rear-wheel drive assists with weight distribution to enhance overall performance and general handling.
- The engine power is sent to all four wheels.
- 4WD improves the vehicle’s ability to handle severe road conditions; i.e. snow, rough terrain, steep slopes (with a heavy car or load).
- Provides more control, stability, traction, and overall handling than 2WD.
- 4WD helps to ensure safety during rough driving conditions due to the above reason.
- Some newer systems will automatically divert power from the wheel or wheels that are slipping to the ones that aren’t to further help with control, stability, and traction.
- Some systems also have lock differentials, which ensure that wheels on the same axel keep the same speed, maximizing traction.
- The most common vehicles that come equipped with, or frequently use, 4WD are trucks and SUVs.
When Should you Use 4WD?
As you already know, 4WD is intended for use when driving on any road or in any condition that could be considered “rough” or “severe.” Here are the conditions that fall into this category:
Off-Roading, in general: Off-roading is a term that simply refers to anything not pavement. Typically, the term is used to refer to going on obscure trails that are known for being difficult to travel. Realistically, any time you take your vehicle off a paved road, it’s probably a good idea to turn on your 4WD. For specific instances, continue reading.
Poorly packed gravel: Loose gravel can be a nightmare to drive on, especially in harsh weather. This is even more true for gravel that sees a lot of rain shift, as it may create deep, muddy holes for your vehicle to get stuck in. If you’re driving down a road and the car feels like it’s losing traction, or you see a giant and muddy puddle, it’s time to turn on the 4WD.
Snow or ice: Everyone knows about the trouble with snow and ice. When the roads get slick, front-wheel and rear-wheel drive can both cause problems for traction and send your car hurdling into the nearest ditch, tree, or river. If it’s snowing, and especially if you suspect ice, make sure to use your 4WD.
Mud: As mentioned with gravel, mud can be a sneaky trap for any vehicle. Whether you are off-roading or backing into a grassy yard to leave a driveway after some rain, 4WD will prevent your vehicle from getting stuck.
Sand: Sand can be just as tricky as loose gravel or mud, and you might not expect the problems it can cause. Whether you’re planning on driving around the beach, or even just over some wet sand, turning on your 4WD can give some much-needed traction.
Steep hills or mountains: If you’re driving on a paved road and the weather is sunny, you probably won’t need 4WD. However, if it’s been raining or snowing, or you’re on other terrain, 4WD can prevent you from sliding down when you want to go up; or even from going down too fast.
When stuck: Getting stuck in a ditch or mud can make you spin tires for ages. Instead of wasting all that time, and risking damaging your tires or even your vehicle, switch on 4WD. It will get you out of there in no-time. Also, it’s worth pointing out, using 4WD from the start might have prevented the problem from happening to begin with.
Towing heavy loads: If you’re towing a trailer or have a heavy load in the bed of your truck, it might be a good idea to turn on 4WD. When towing or transporting heavy loads, 4WD will be necessary for any non-paved road, driving on extremely steep inclines (especially if they aren’t paved), and severe weather. Doing so will increase traction and increase stability and control, helping to ensure that nothing goes awry during transport.
When Not to Use 4WD
While 4WD is better for control, stability, traction, and overall handling, sometimes it will actually be better to use 2WD. Here are some such instances:
- When driving on the highway
- When driving on any smooth, flat, asphalt road
- During good weather conditions
- When driving at high speeds
- When driving conditions are getting unsafe, but are not quite rough or severe; many vehicles also have a traction/stability control setting that can be used first
Disadvantages to 4WD
In the above circumstances, 4WD poses some significant disadvantages in terms of vehicle capability and safety. These include:
- Lower gas mileage because power is produced for 4 wheels instead of just 2; driving on the highway or on smooth, dry roads will just cost more in the long run.
- Driving at high speeds can be very dangerous because the wheels in the front and back will always turn at the same speed (if you have lock differentials); if you hit a corner, you may wreck or even flip your car
- If you use it unnecessarily, you put extra pressure and wear on your drivetrain, differential locks (if you have them), and gears.
4WD vs AWD – Does It Matter?
Many people will use 4WD and AWD interchangeably. While at one point they were virtually the same, during the early years of vehicles, they no longer are. The differences might not seem significant but, in truth, are somewhat important in terms of their capabilities.
- Part-time and full-time options.
- Part-time 4WD typically requires you to turn it on and off manually; this gives you the option to control it as you will, but also means you must remember to do so.
- Because it is manual you also have the option of 4W-hi or 4W-low.
- Newer vehicles may also have a part-time system that turns on for you.
- If you have this newer part-time system, the car may choose to divert power to specific wheels; i.e. the wheels without traction won’t be powered, those with traction will be.
- Best at handling extremely adverse conditions.
- Expends gas at a much higher rate than any other drivetrain due to heavy usage.
- Typically, 4WD vehicles have a heavier suspension that may cause bumpier rides.
- Part-time and full-time options.
- Part-time AWD typically turns on automatically as needed, determined by the vehicle.
- AWD has a higher vehicle variety in terms of purchasing options; you can find them on many cars
- Good for dangerous weather or rough road conditions, but not the extremes; not typically meant for heavy off-roading
- Like 2WD, is typically better on gas, especially if you have part-time.
- If you have the part-time system, the car may choose to divert power to specific wheels
What is the Difference Between 4WD Hi and 4WD Low?
4WD systems can be more complex than simply turning them off and on. Many also have a high and low setting. So, when exactly is each used?
- A similar gear to 2WD, just using all 4 tires.
- Meant for normal speeds.
- Used on highways or smooth roads during poor weather; i.e. rain, snow, ice.
- Also good on level, but loose, gravel roads, packed sand, and mud.
- A lower gear-ratio with more power and torque than 2WD in addition to using all 4 tires.
- Intended to be used for serious off-roading; deep sand, extreme snow or ice, pools of water, deep or extremely slippery mud, climbing rocks, or ascending/descending hills.
- Speed must be kept low as the grip on the road is not increased; you’re simply applying more torque to maximize the traction you already have.
- Typically, the wheels also turn slower in 4L than 4H in order to accomplish this maximization of vehicle traction and power.
Frequently Asked Questions About 4WD
There are many questions that people have about 4WD, whether it be double-checking what one already knows or seeking more detailed information. Here are some frequently asked questions and their answers:
What 4WD Setting Should I Use for Sand?
It depends on how well-packed the sand is. Unless you are on a very well-formed trail that is packed in good and tight, with very little loose sand, I would suggest using 4WD-Low. It is unlikely you will travel through sand very quickly, and 4L will give you the most power to ensure you make it through without getting stuck.
Is 4WD Good in Snow?
4WD excels in Snow. If you have the option between high and low, 4H will allow you to continue traveling at normal speeds through early snowfall, whereas 4L will prevent you from getting stuck in deep snow or make traveling over thick ice patches easier.
It is important to note that 4WD will not prevent your car from slipping, nor will it help you brake easier or give more stability for turning (especially at fast speeds). You will still need to drive at the appropriate speed for your weather conditions.
That being said, AWD will also do well with most snowy or icy conditions and, except for in extremely deep snow, will fair almost as well as 4WD.
Do You Need 4WD for Off-Roading?
This is another question that depends on the situation and type of off-roading. If you are planning on climbing over rocks, going through lots of water, or traveling through deep mud, 4WD will likely be necessary to prevent your vehicle from getting stuck. If you are just going over some gravel or on a relatively well-formed trail, then you can likely manage with 2WD.
What Are the Best 4WD SUVs?
Picking the best SUV may depend on exactly what you are looking for in terms of vehicular capability. Some of the top choices for 4WD SUVs include: Jeep Wrangler, Toyota 4Runner, Lexus GX, Mercedes Benz G-Class, Toyota Land Cruiser, Jeep Grand Cherokee or Jeep Cherokee, and Toyota Sequoia, to name a few.
In general, Jeep SUVs have a great reputation in terms of serious off-roading as well as your standard highway driving.
4WD should be used any time that you are driving on rough or difficult terrain, be it snow and ice or mud and sand. 4WD is also useful for towing large, difficult to handle loads, such as a heavy trailer. While using 4WD can certainly help with traction, stability, and control, it is important to remember that you do not become invincible. To ensure safety, drive at appropriate speeds to your road condition and driving circumstances and keep an eye out for ice, large puddles of water, or anything else that may cause you to lose traction.
Hi, I am Brad. Car Independent is your source for independent views on cars and car accessories. Whether you looking to buy a new car or something cool for your car, you have many options. My aim to help you make the best-informed choices.