How Many Axles Does a Car Have?

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The number of axles a car has depends on knowing two factors. First, which type of axle does the car use? Most solid-axle cars will have a maximum of two, while a constant velocity axle (CV axle)-equipped car will usually have up to four. Next, is the vehicle two- or four-wheel drive? More driven wheels mean more axles. The Jeep Wrangler, for example, has two axles because it's four-wheel-drive and has solid axles. The front-wheel-drive Honda Civic will have two CV axle shafts, while something like a Subaru Crosstrek will have four CV axles because it's all-wheel-drive.

Some passenger vehicles, such as the Mercedes G 63 6x6, have even more axles — three to be exact — with one solid axle in front and two solid axles in the rear for a total of six wheels. Some heavy-duty military and construction vehicles can have up to eight driven wheels, which means they could have between four and eight axles, depending again on which type of axle design the vehicle uses.

That's the short answer, but for those interested in what an axle means for a given car's driving experience and capabilities, keep reading for more information.

Jump to:
What is an axle?
Types of axles
Are more axles better?
How many axles is right for you?
Axle ratio

What is an axle?

Throughout the history of the automobile, there have been a handful of different types of axles used on mainstream cars, but before we get to that, we should explain what an axle is. In the simplest terms, an axle is a spinning shaft that transmits torque from your vehicle's transmission to its wheels. Without axles, you and your car wouldn't be going anywhere.

Types of axles

While there have been a handful of axle designs used throughout the history of the automobile, modern vehicles use one of two designs. The first and simplest of these is the solid or live axle.

Solid (or live) axle: This design houses the spinning axle shafts inside an axle tube, which has no ability to articulate. The upside of a solid axle is the simplicity and robustness of its design and its use in off-road applications. A solid-axle vehicle generally has more suspension articulation than a vehicle with our next kind of axle, the CV shaft.

CV axle (or CV shaft): A CV shaft, or constant velocity shaft, is used in vehicles with an independent suspension. In this design, the shafts are jointed at both ends to allow the wheels to move independently of one another. This design also has the CV axles out in the open with the constant velocity joints usually living inside a grease-filled rubber boot. The advantages of a CV axle include a smoother ride with nicer steering due to the ability of the wheels to act independently of one another. This means, for example, that if you hit a pothole with one wheel, the other won't be as disturbed by the impact.

Are more axles better?

Having more driven wheels on a vehicle can be a double-edged sword. If you live in an area with lots of snow and rain, having all-wheel drive or four-wheel drive may be helpful to you, but having those extra axles introduces more points of failure and can mean increased maintenance costs. Conversely, having a car with only front- or rear-wheel drive will mean having fewer parts to fail, but you might not be able to deal with a snowy commute as well as you would if you had all-wheel drive.

If you have to haul a great deal of cargo — say, for example, you're driving a semi-truck — having more axles gives you more traction and grip, making it safer and easier to move said cargo down the road. On the flip side, having more axles again means increased maintenance and repair costs. Another fringe downside to the added weight of a four-wheel or all-wheel-drive vehicle is that it often means that it will have reduced carrying capacity. After all, if you are spending more energy hauling a heavy vehicle around, there will be less left for hauling your stuff.

How many axles is right for you?

Ultimately, the answer to this question comes down to the kind of driving you do, the climate in which you do it, and your budget. Having four-wheel drive or all-wheel drive will give you more ability to traverse difficult terrain or deal with wet and snowy conditions, but the vehicle will also use more fuel, weigh more, and go through wear-and-tear items such as brakes and tires more quickly as a result. All-wheel-drive and four-wheel-drive vehicles are also typically more expensive to purchase than their two-wheel-drive counterparts.

The good news is that if you aren't comfortable with the trade-offs that come with having a car with more axles, you might be able to get by with two-wheel drive and some practice in low-traction situations. Increasing your skill level as a driver will get you out of more situations than you might expect.

Axle ratio

Now that we've figured out how many axles are right for us, it's possible that we'll need to pick an axle ratio. This is common on full-size trucks because a higher or lower axle ratio will drastically alter the driving characteristics of a vehicle. A higher ratio — take 2.97, for example — means that the engine turns fewer times to make the drive axles do a complete rotation. This "taller" ratio gives the vehicle a higher top speed and often can increase fuel mileage since the engine isn't turning as fast at a given speed.

A lower gear ratio — 4.11 is common in performance cars — will have the engine turn 4.11 times for every time the drive axle makes a single rotation. This results in a lower top speed, but because it multiplies your engine's torque, it will usually lead to quicker acceleration. Because the engine is spinning more quickly at a given road speed, fuel economy will typically be worse with a lower (aka shorter) gear ratio. This torque multiplication also benefits those drivers who tow regularly, offering more brisk performance when pulling a heavy load.