What is an axle? An axle is a central shaft that connects two wheels and transfers power from the car engine to propel the wheels.
The axle is a critical component of a vehicle. It carries the weight of the vehicle, plus the passenger, cargo, and the extra force when accelerating and braking.
The axles are either connected to the vehicle wheels or rotate with them. They work in harmony with the bearings that are fixed in the middle of the wheels for a seamless and noiseless driving experience. How many axles does a car have, anyway?
This looks like a pretty straightforward question. But the answer is not that simple. Why did I say so? The answer is tricky because of the way automakers design vehicles.
This article will explain how many axles are on SUVs, cars, vans, sedans, and trucks. It’ll also explain the types of axles and their working principles.
How many axles does a car have?
Because of car designs, there are several axles on a car. The number of axles on a car depends on the vehicle design. Most passenger cars have two axles to drive the wheels. Bigger vehicles like trucks and vans may have more axles.
It’s pretty easy to determine the number of axles in a vehicle. Stand at the side of the vehicle and count the number of pairs of tires it has. So, if you are asking, “how many axles does a Honda Civic have,” the answer is two.
Most cars have four tires in total and that is two sets of tires. From the definition of an axle above, an axle connects two opposite wheels and propels engine power to move the wheels.
Two sets of tires with one in the rear end and one in the front wheels equal two axles.
Types Of Axles And Working Principles
There are several types of axles in a vehicle. But before we go into that, let’s look at the factors that determine the type of axles in your vehicle.
Several factors play a big role in determining the types of axles a vehicle needs. These are;
The amount of force produced and the technical requirements. In some vehicles, manufacturers design customized axles that meet the specifications of a car. In other vehicles, manufacturers have pre-defined axles in standard formats.
Customized axles are best for most cars since they have a personalized control on the wheels for better handling. Aside from personalized control, they can tune the wheel’s torque and speed to a reasonable extent.
Types Of Axles
Vehicle axles are categorized by their position in front and rear wheels, and by their functions as well. The two main functions of an axle are to carry the weight of a vehicle and transfer engine power to the wheels. There are three standard types of axles:
As the name suggests, front axles are located in the front and they connect to the front wheels. They play a major role in processing shocks from road bumps, potholes, and uneven road conditions. They also assist a vehicle steering system.
These axles comprise four components, which include the beam, the track rod, the swivel pin, and the stub axles. Automakers made these types of axles from nickel steels or carbon steel, and that is why they are as sturdy as possible.
Manufacturers connect stub axles to the front wheels. It is also attached to the front axles via a kingpin.
Manufacturers engineer the rear axles to deliver power to the wheels, and they come in two halves. They are half-shafts that connect to the rear differentials. In most vehicles, rear axles rotate with the wheels.
Types of front axles
There are two types of front axles.
Live front axle: Live front axles rotate with the front wheels. They transmit power from the gearbox to the front wheels.
Dead front axle: Unlike live front axles, these axles are stationary. They don’t rotate with the wheels. Most dead differentials and axles are covered with housing that protects them from water.
Types of stub axles
There are four types of stub axles.
Elliot: This type of stub axle connects to the front axles using a kingpin, yoke, and cotter.
Reverse Elliot: As the name suggests, this type of stub axle has an opposite layout with Elliot stub axles.
Lamoine: A Lamoine stub axle has an L-shaped spindle instead of the yoke type hinged in the Elliot stub axle.
Reversed Lamoine: According to the name, it has an opposite arrangement of a Lamoine stub axle.
Types of rear axles
Rear axles come in different types. The mounting and support type determines the type of rear axle in a vehicle. Rear axles come in three types.
Semi-floating axle: This type of axle connects the wheel to the differential flange. It has two bearings. One bearing goes inside the axle casing, while the other supports the axle shaft.
Semi-floating rear axles have to be larger than other options to produce the same torque with them. They are commonly seen on SUVs, small passenger cars, and lightweight trucks.
Full-floating axles: As the name suggests, full-floating axles effectively float in place. It has two bearings, like the semi-floating axle. Its only function is to transmit torque to the wheels. These axles are seen on heavy-duty trucks, like fire trucks. Some mid-size trucks with high towing capacity come with full-floating axles.
Three Quarters floating axles: This type of floating axle is less effective than full-floating axles. However, they are more effective and reliable than semi-floating axles. It’s very effective in handling driving power and side thrusts. It also maintains wheel alignment.
Q: Does a car have 2 or 4 axles?
There’s no straightforward answer to this – since vehicles come with different types of axles and the number of axles on vehicles varies. Factors like the technical requirements and the amount of force produced determine the type of axle a vehicle has.
Some vehicles have customized axles that work best because they adjust the speed and torque, and fit the vehicle specifications to a finer degree. Vehicles have different suspension systems, like dampers to link the wheels to the chassis, mechanical connections, and springs. Just as they have different types of axles.
Q: How many axles does a 4WD car have?
Small passenger cars, irrespective of the drive-wheels, have 2 axles, and AWD vehicles are no exception. Similarly, if you’re wondering, ‘how many axles does AWD have?’ The answer is 2.
However, it is important to note that some AWD and 4WD vehicles can have more than 2 axles. As indicated above, the reason is that vehicles come with various designs.
Q: What is considered a 3 axle vehicle?
In simple terms, a car is considered a 3 axle vehicle if it has 3 axles. Each of these axles plays their roles effectively. Examples of 3 axle vehicles are many straight trucks with a pair of rear axles to sustain the extra weight of the cargo, a Greyhound bus, and some tractors with semi-trailers.
Q: What is a 1 axle vehicle?
A 1 axle vehicle, popularly known as a single truck, is a light or semi-truck with 1 drive axle on the rear wheels. These trucks are commonly used in delivering lightweight goods like beverages on the street.
They may not be as strong as tandem semi-trucks, but they offer better gas mileage than the tandem semi-trucks.
Q: What is a 5 axle vehicle?
Semi-truck is commonly known as 5 axle vehicles. These are the legal semi-truck combinations across North America. Depending on the goods you want to transport, these trucks can pull flatbeds, van trailers, and refrigerated trailers.
You can increase the amount of weight that these trucks can carry by separating the trailer axles apart from one another.
The gross weight for this truck combination is 80,000 Ibs when traveling interstate in the US states. However, all provinces in Canada and some states in the United States will allow heavier weight.
Q: Do all cars have 2 axles?
Most cars have two axles to transmit power to the wheels and carry the weight of the vehicle. However, bigger passenger cars that have more wheels and can carry more passengers have more axles. This explains 2 axle vehicle meanings and all you need to know.
How different types of car axles work YouTube
More than asking ‘how many axles does a car have,’ it’s essential to know the types of axles and their working principles. Like other suspension systems components, you need to learn about them since you’d not be able to drive your vehicle when they damage.
It’s quite true manufacturers engineered them to carry the vehicle weight. Shocks from road conditions and high impact from collisions can weaken them. Having a basic idea of the working principles of your vehicle components will help you pinpoint where a fault is coming from when your vehicle projects one.