Diagnosing and Maintaining Automatic Locking Hubs on Four-wheel Drive Vehicles

Automatic locking hubs are one of the most important features on four-wheel drive vehicles. Their job is to release the front wheels when you don't need the four-wheel drive system. Several benefits come with the action of the automatic locking hubs. First, releasing the front wheels when the vehicle doesn't need to be in four-wheel drive reduces wear and tear of the four-wheel-drive components. Secondly, you also get to save lots of fuel over long distances because the drivetrain demands less power from the engine. In this piece, you will learn about diagnosing and maintaining the automatic locking hubs on your four-wheel drive vehicle.

Common Problems of the Automatic Locking Hub

The most common problem affecting automatic locking hubs is a failure to engage. It is difficult for any driver to detect this when it happens until the vehicle is stuck in mud or deep sand. It's only then that you will realise that the front wheels are not doing anything to steer the vehicle out of the mud or sand. Alternatively, some four-wheel-drive setups will produce a grinding noise when you engage the four-wheel drive system, making you think there is a mechanical problem with the front differential or transfer case.

Most failures of the automatic locking hub occur due to mud, worn parts and rust inside the assembly.

Examining the Automatic Locking Hub

Checking your automatic locking hub regularly will prevent unexpected mechanical problems. The tests are rather simple. Start by engaging the transmission of the vehicle in park and setting the parking brake. After that, use a jerk to raise the chassis of any of the front wheels and leave the other front wheel on the ground. If the transfer case is in two-wheel drive, the hubs should have released the wheels, allowing the raised wheel to spin freely when you turn it by hand. If the axle shaft turns with the wheel in this case, it means that the hub failed to disengage.

If you want to confirm the engagement, turn the axle shaft backwards. It should make the hub lock. Try spinning the vehicle's wheel with your hand again. The wheel and axle shaft should turn simultaneously. If this does not happen, your automatic locking hub needs thorough disassembly and service.

Maintenance and Service

It's important to engage the services of qualified mechanics to service and repair your automatic locking hub. There is no standard method of repairing the automatic locking hub. The procedures vary from one manufacturer to another; this is stuff best understood by skilled four-wheel drive mechanics.  

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