(Updated on November 3, 2022)
Axles are what give vehicles the ability to rotate their wheels. Some vehicles have it where the axles are attached to the wheels while others have the axles attached to the body.
In addition to giving the wheels the ability to rotate, axles may also support the weight of a vehicle too. This is true if you have either a full floating axle or a semi floating axle. The type of axle which gets inserted into your vehicle will depend on the type of vehicle and what it’s overall purpose is.
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The full floating axle has the wheel hub and rod attached together. The axle housing has the wheel mounted onto it, rather than onto the axle rod. This means the rod doesn’t get the bending effect like with the semi floating axle.
The rod will get the torque effect only, which gets transmitted to the wheels from the differential. Because of this, the assembly endures the weight of the vehicle rather than the axle shaft. This is how the full floating axle is able to support so much more weight than the semi floating axle.
The types of vehicles that will contain full floating axles are big trucks, pick-up trucks, and SUVs. These are all vehicles that are built to haul an extra load of weight behind them.
With a full floating axle inside these vehicles, they’ll be able to carry this weight without any setbacks. Plus, a full floating axle will make your vehicle safer to drive because the wheels are not attached to the axle. They are attached to the wheel hub. This means if the axle were to break, the wheels would stay attached and continue to rotate on the road.
The big downside to a full floating axle is that it costs more money to manufacture than a semi floating axle. This means vehicles with a full floating axle are going to be more expensive.
So, if you really need a vehicle for the purpose of hauling heavy items, then a full floating axle is definitely worth the investment.
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A semi-floating axle is an axle shaft that is connected directly to the wheels and transfers power to them from the differential. One side of the bearing has the axle housing and the other side has the axle rod. This allows the rod to endure the weight of the vehicle and endure the torque and bending effect.
Since the rod is enduring the weight and not the assembly, it is able to handle more weight than a non-floating axle but not as much weight as a full floating axle.
Most vehicles on the road which have 4-wheel drive will likely contain a semi-floating axle. These axles are not meant for vehicles that carry too much weight, such as SUVs and pick-up trucks.
Semi-floating axles are meant for lighter cars which people drive every day to work or around their town. The axles themselves are lighter which makes them very easy to install in a vehicle.
Finally, vehicles with semi floating axles are cheaper than those with full floating axles. There is no sense in spending the extra money on an SUV or pick-up truck if you’re not going to be hauling anything on a regular basis.
A semi floating axle will let you carry some weight, though, and you’ll still save money too. The only downside is that if the axle shaft breaks while you’re driving, the wheels will come loose because they’re connected to the shaft.