Car Services and Parts

Over the decades, vehicles have become increasingly complicated to operate and repair. Advancements in technology and design have made our cars safer and more environmentally friendly but they have also increased the complexity of their makeup. Of all the various parts of a car, the universal joints or u-joint is a component that has seen little change over time. It is still a critical drive train component that allows for transfer of power throughout the vehicle. 

Learn more about universal joints

What are universal joints?

Whilst universal joints are used for many other applications besides in autos, they are commonly found in many types of cars that utilize a trans-axle to transfer power from the engine and transmission back to the rear wheel and axle assembly.

The joint itself connects rigid rods that transmit rotary motion from one end of a vehicle to another. A typical u-joint consists of a pair of hinges connected relatively close to one another and oriented at ninety degree angles to one another. They are connected by a shaft that is called a cross shaft.

How does a u-joint work?

U-joints are primary responsible for transmitting rotary motion so when a shaft spins, the u-joint also spins transferring that motion and torque power to another component it is connected to on the other end. In vehicles, the u-joint connects a long shaft called the universal shaft. On the back end of the u-joint, an assembly called a trans axle is connected. This trans-axle is a metal housing the contains various sizes of gears that redirects rotary motion to wheels on the rear of a vehicle.

Once this whole dance is in motion, the wheels turn and the car goes down the road. The u-joint acts as a liaison between two components that rely on each other to transfer power from the engine to the wheels. U-joints work well in this capacity because they are flexible as opposed to the rigidity of the universal shaft.

Is a u-joint hard to replace?

In general, a u-joint repair is considered an advanced mechanical repair task that should be performed by a certified professional. Gaining access to a u-joint often requires the use of a lift and air-powered tools to remove the joint from the shaft. It also takes a trained eye to determine if the u-joint is the cause of any mechanical issue and if replacing it would solve the problem. U-joints themselves are relatively inexpensive parts.