Axle shafts are heavy-duty, load-bearing components used in motorised vehicles. Also called CV axles or half-shafts, these components transfer rotational force from the vehicle’s transmission system to the wheels attached to the axles. Axle shafts must support heavy loads by design, including cargo, riders, and the vehicle’s own mass. While they are built to handle heavy weights, it is possible to overload the component and force it to warp or break from the strain. Similarly, physical impact from collisions, potholes, and rough roads may cause damage.
Drive axles are crucial drivetrain components that connect a vehicle’s transmission to the vehicle’s wheels. Axle shafts are primarily responsible for transferring the transmission’s rotational force and power to make the vehicle move. When the force from the transmission causes the axle shaft to rotate, the wheels connected to it also turn. Every axle shaft has a differential between two half axles and two universal (UV) joints.
Ultimately, axle shafts allow vehicles to roll and facilitate controlled movement of their wheels. Without reliable drive shafts, the wheels of the vehicle wouldn’t move properly or at all.
The type of axle shaft varies depending on the requirements of the vehicle type, and each axle shaft handles different types of stress. This factor depends on the length of the axle shaft relative to the position of the vehicle’s hubs and bearings, as well as how the vehicles are designed to attach to the axle shafts.
These are three most common axle shaft types:
1. Semi-Floating Axle Shafts
This design has flange faces on both outer ends of the axle shaft. These faces attach directly onto the associated wheels.
2. Fully Floating Axle Shafts
Instead of having flange faces that directly connect the axle shaft to the wheels, this style of axle shaft has hubs between the two components. Each wheel connects to a hub, and that hub rotates on roller bearings attached to a spindle at both ends of the axle shaft. The roller bearings are tapered and face opposing directions, and the hubs and bearings handle the vehicle weight to take strain off the axle bearing. Without the need to support the weight of the vehicle and its cargo, the axle bearing “floats,” instead only having to withstand the transmission system’s torque.
3. Three-Quarter Floating Axle Shafts
These axle shafts feature elements from both semi-floating and full floating axle shaft designs. Three-quarter floating axle shafts have bearings positioned between the axle casing and hub axle shaft. However, the bearings remain protected from shearing or bending forces.
Drive shafts and axle shafts are both types of vehicle components that transfer power to make a vehicle move. However, a drive shaft is a hollow metal tube with universal end joints that handles the power transfer from the transmission to the rear differential gearbox. The axle shaft then transfers that power onward to the wheels.
Axle shafts are solid rods with teeth cut into both ends. Whereas drive shafts visibly run down the centre of the vehicle, the axle shaft is concealed in the perpendicular housing that runs from the rear differential gearbox to each wheel.