Rear axle shaft

Types of Rear Axle Shaft

The rear axle shaft is one of the most important components in a car. It is the part that transfers power from the rear differential to the rear wheels, making it possible for the rear wheels to rotate and drive the vehicle forward or backward. The rear axle shaft also helps support the weight of the vehicle. Without the rear axle shaft, the rear wheels would not move, and the car would not drive.

There are several types of rear axle shafts, which include:

• Semi-floating rear axle shafts: This type of rear axle shaft is commonly used in most passenger vehicles. The semi-floating rear axle shaft has one wheel bearing placed between the differential and the outer wheel hub. This design allows the rear axle shaft to support the vehicle's weight and bear the loads from the wheels when driving. Most of the weight and stress is transferred to the wheel hub. The semi-floating rear axle shafts are more common and affordable.
• Full-floating rear axle shafts: The full-floating rear axle shaft is mostly found in heavy-duty trucks and some sports cars. Unlike the semi-floating rear axle shaft, the full-floating rear axle shaft has wheel bearings placed in the middle of the wheel hub. This design allows the axle shaft to float freely and does not put much stress on the axle shaft. With this design, the force from the wheels and the vehicle's weight is transferred to the wheel hub and the vehicle's frame. The full-floating rear axle shafts are suitable for vehicles that carry heavy loads.
• Independent rear suspension systems: The independent rear suspension system is commonly found in modern vehicles. In this type of rear suspension system, each rear wheel is attached to the vehicle body with its suspension components. This design allows the rear wheels to move up and down independently. The independent rear axle shafts provide better stability and traction on rough roads. The independent rear axle shafts are ideal for off-road vehicles.

Understanding the different types of rear axle shafts can help vehicle owners choose the best replacement parts for their cars. Factors like load capacity, driving conditions, and road quality can also determine the type of rear axle shafts suitable for a vehicle.

Specifications and Maintenance of Rear Axle Shaft

• Regular Inspection

  Visual inspection of the rear axle shafts should be performed regularly. Look for any signs of wear, damage, or leakage of lubricant. Any cracked or damaged boots should be replaced immediately to prevent contamination.

• Lubrication

  The proper type and amount of lubricant should be used in the rear axle differential as specified by the vehicle manufacturer. Check the lubricant level regularly and top up as needed. The lubricant helps reduce friction and prevents wear on the axle components.

• Torque Specifications

  When installing or removing axle-related components, always use the specified torque values in the owner's manual. Over-tightening or under-tightening can lead to failures.

• Alignment

  After any suspension or axle work, ensure that the wheel alignment is checked and adjusted if necessary. Proper alignment helps the rear axle shafts wear evenly.

• Avoid Overloading

  Do not exceed the vehicle's maximum load rating. Carrying excessive loads puts extra stress on the rear axle shafts and can lead to premature failure.

• Seals and Bearings

  Inspect seals and bearings around the rear axle shafts for leaks or play. Worn bearings should be replaced, and any leaking seals should be changed to keep the lubricant inside the axle.

• Driving Habits

  Driving habits also affect rear axle shaft longevity. Start off slowly when fully loaded or towing. Avoid sudden accelerations, which put extra strain on the axle components.

• Professional Inspection

  If any unusual noises, vibrations, or issues with wheel hub bearing or differential operation are noticed, have a qualified mechanic inspect the rear axle shafts and related components immediately. Early detection of problems can help avoid more expensive repairs down the road.

How to choose rear axle shaft

When selecting rear axle shafts for retail or wholesale, it's important to consider several factors to ensure that the needs of the target customers are met. Some of these factors include:

• Application

  Consider the specific application for the rear axle shafts. Will they be used in a light-duty truck, heavy-duty towing, or off-road applications? Different applications have different load capacities and durability requirements. Determine the intended use of the vehicle to make the right choice.

• Material

  Rear axle shafts are typically made of steel or iron. Steel is a strong and durable material that can handle heavy loads, making it a popular choice for heavy-duty applications. Cast iron is more brittle than steel, so it is not as commonly used in modern rear axles. However, cast iron can be found in some older vehicles. Consider the advantages and disadvantages of each material before selecting a rear axle shaft.

• Length

  The length of the rear axle shafts should be appropriate for the vehicle's specifications and modifications. Axle shafts that are too short or too long can lead to mechanical failures. Measure the distance from the center of one wheel hub to the center of the differential housing to determine the correct length.

• Differential compatibility

  Ensure that the rear axle shafts are compatible with the vehicle's differential. Different differentials have varying designs and specifications, so selecting axle shafts that match the differential gears and housing is important.

• Wheel bearing size

  The rear axle shafts connect to the wheel bearings, so their sizes should be compatible. Measure the inner diameter of the wheel bearings or consult the vehicle's specifications to determine the correct size.

• Load capacity

  Consider the load-carrying capacity of the rear axle shafts. If the vehicle will be used for heavy towing or carrying large loads, selecting axle shafts with a higher load capacity is important to prevent premature failure.

• Quality and durability

  Look for rear axle shafts from reputable manufacturers known for quality and durability. Reading reviews and seeking recommendations can help identify reliable brands. Investing in high-quality axle shafts can improve performance and longevity, reducing the need for frequent replacements.

How to DIY and Replace Rear Axle Shafts

Replacing the rear drive axle shaft may be a complicated process. However, with the right tools and professional knowledge, it can be done. Below are the steps for replacing rear axle shafts:

Tools needed:

• Safety equipment
• Jack and jack stands
• Wheel chocks
• Socket set
• Torque wrench
• Hammer
• Puller tool (if necessary)
• New rear axle shaft
• Lubricant (if recommended by the manufacturer)

Steps:

• 1. Safety measures: Ensure safety by parking the vehicle on a leveled ground, engaging the parking brake, and using wheel chocks. Put on the safety glasses and gloves.
• 2. Raise the vehicle: Use the jack to lift the vehicle and place it on the jack stands.
• 3. Remove the wheel: Use a socket set to remove the wheel nuts, then take the wheel off.
• 4. Remove the brake components: Depending on the vehicle, one may need to remove the brake caliper and brake rotor. Follow the manufacturer's manual to disconnect the brake components safely.
• 5. Disconnect the differential: Look for the bolts that hold the rear axle shaft to the differential. Use a socket set to loosen and remove the bolts. Depending on the model, one may need to disconnect other components, such as the wheel bearing or hub assembly, to access the axle shaft.
• 6. Remove the axle shaft: Pry the axle shaft out of the housing using a hammer and a puller tool. It may require some effort, as the axle shaft may be lodged in the housing.
• 7. Prepare for installation: Clean the housing and inspect the components. Ensure that all the sealants and old lubricants are removed before installing the new rear axle shaft.
• 8. Install the new axle shaft: Apply a lubricant to the splines of the new axle shaft (if recommended by the manufacturer). Then, carefully slide the new axle shaft into the housing.
• 9. Reconnect the differential: Reconnect the rear differential to the axle shaft using the bolts. Ensure that the bolts are tightened to the manufacturer's torque specifications.
• 10. Reinstall other components: Reinstall other components disconnected in step 5. Reattach the brake caliper and brake rotor.
• 11. Lower the vehicle: Remove the jack stands and lower the vehicle off the jack.

Q and A

Q: What is the function of the rear axle shaft?

A: The rear axle shaft's primary function is to transfer power from the rear differential to the rear wheels to enable the vehicle to move in a controlled manner.

Q: How do people know that their rear axle shafts are bad?

A: The common rear axle shaft failure symptoms include noise and vibration during turning or acceleration, uneven tire wear, and the car pulling to one side. Visual leakage of grease or oil and limited wheel movement are advanced signs of a bad rear axle shaft.

Q: Can people drive with a broken rear axle shaft?

A: No, a broken rear axle shaft is a severe mechanical problem that immobilizes the rear wheels. Driving with a broken axle can cause further damage to the vehicle, including the suspension and drivetrain. To avoid such problems, people should address rear axle shaft issues as soon as they arise.