Depending on how mechanically inclined you are, you may not have come across the term universal joint before. Also known as a U-joint, this component is key to keeping your car running. Alongside the resulting transmission fluid leak, a broken U-joint can seriously damage your vehicle’s driveshaft, brake line, transmission line, and many other parts of the car.

It is, therefore, important to understand what a universal joint does in your car and how to spot any signs of U-joint trouble before things get disastrous. Knowing a bit about the correct operation, as well as the maintenance of universal joints, can save you a lot of money overall when it comes to repairs.

That’s why we’ve produced this easy guide! You’ll learn all you need to know about this car part, the signs of U-joint trouble and how to replace this car part if needed.

What Is a Universal Joint?

Universal joints, or U-joints, are X-shaped car parts made of steel with a bearing cap on each end. They connect the rigid driveshaft of the vehicle to the transmission and allow it to turn freely.

Universal joints are part of a system that enables the crankshaft to deliver rotational energy to the wheels. Thanks to the adjustable connection to the driveshaft, the driveshaft can move up and down, as well as an angle when you drive on uneven roads.

universal joint

Can You Diagnose a Bad Universal Joint?

As is the case with everything, your car’s U-joint will experience damage through general wear and tear over time. If it’s allowed to get too bad, a faulty universal joint can cause the driveshaft to separate from your car and cause severe damage or even an accident.

With, there are a few warning signs you can look out for to get the heads-up that your car’s universal joint needs some attention. Addressing universal joint issues ahead of time can save you from dealing with costly transmission fixes further down the line or being stranded in the middle of nowhere when your car breaks down.

 Squeaky Noises

Bearing components within your universal joint need to be adequately lubricated to function correctly. As the driveshaft rotates and the bearing portion twists, the grease lubricating the universal joint will wear off gradually. This then causes the bearing component to dry up and for there to be metal-on-metal contact, causing that squeaking sound every time the U-joint rotates. It is often easy to dismiss this noise, though, as it usually disappears once the vehicle gets moving. However, the sound shouldn’t be ignored as it is a clear indication that you need your universal joints serviced by a professional.

 Ringing Sounds

Another sound that may be a sign that your universal joint is on its last legs is a slight clunk followed by ringing each time you shift into reverse. This can be caused by the universal joint having enough space to allow the driveshaft to rotate but stopping abruptly when it is reversed. At this stage of the game, lubricating the universal joint won’t do much to reduce damage, but it may extend the component’s service life.

Leaking Transmission Fluid

If you notice fluid leaking from your vehicle’s rear transmission, it is usually a sign that you’ve got a faulty universal joint. When a bad universal joint causes damage to the car’s transmission tail shaft bushing and output shaft seal, it will result in a fluid leak. However, it is important to note that there are several other reasons you might experience a leaky transmission. Regardless, it is essential to have the vehicle inspected by a mechanic to ascertain what needs to be fixed.

Widespread Vibration

Experiencing vibration across the whole of your vehicle is typically a sign that the bad universal joint has done such severe damage to the driveshaft, to the point that it is now unbalanced. Of course, there are other reasons why your car could be vibrating, such as your wheels being out of alignment, but vibrations caused by universal joint damage are very frequent and hard to ignore. Dismissing this sign is not a clever idea as a worn universal joint will gradually cause damage to other parts of the car, including the transmission system.

Sudden Stopping or Inability to Start Moving

The final and worst sign of a bad universal joint is when your car stops moving altogether. This indicates that the universal joint has totally broken down; the driveshaft has dropped and can no longer transfer power. Letting things escalate to this stage isn’t an innovative idea, as it is no longer a case of merely replacing a broken universal joint. You’ll have to deal with a damaged driveshaft, which is much more expensive.

How to Change Your Universal Joint

If you suspect that your vehicle’s universal joint may need replacing, it is best to head straight to a certified mechanic to have the car assessed. Getting your universal joint replaced isn’t too costly in the grand scheme of things and certainly far less expensive than the repairs required if your transmission suffers, or you experience driveshaft separation because of the damage from the universal joint failing further.

Of course, if you are curious about the process of replacing a universal joint on a vehicle, this is what typically happens.

Step 1: Access The Driveshaft

The first step in replacing your universal joint is getting to the part. To do this, you’ll need to remove the driveshaft. On some vehicles, you remove the driveshaft by removing the universal joint. If, however, your driveshaft attaches with axle-type bolts, you can proceed to remove that end of the driveshaft.

Step 2: Remove the DriveShaft

If your driveshaft does not have the above type of end, you will need to remove it by removing the two bolts that hold the two halves of the universal joint together. This will cause the driveshaft to come out easily.

Step 3: Remove the Universal Joints Snap Rings or C-Clips

While there are two types of clips (snap rings and C-clips) that may be holding your universal joint together, both are easy to remove, and the steps are the same regardless of which is present on your vehicle. Simply squeeze the ends together with pliers or a special removal tool to remove the snap rings or C-clips. They should come off easily. If they have become corroded, you may need to soak the universal joint with some penetrant to make the process easier.

Step 4: Press the Bearing Joint Out

With the driveshaft out of the vehicle, the next step is to remove the universal joint and its bearings. You’ll need to mount the end in a vice, then tap the bearing through far enough to get the joint to drop out. Firmly tap it until the whole thing is pressed far enough in to be able to pop it out.

Step 5: Remove the Bearing Cup From Your Universal Joint

Now that your universal joint is tapped through, you can remove the bearing cup. This will enable you to remove the loose joint section fully.

Step 6: Insert a New Universal Joint

It is now time to get that old universal joint centre out of there and put the new part in. There’s a chance that your new centre will assemble a little differently from how the old one came out. Don’t stress, most replacement universal joints look a little different. Before you reinstall, lubricate every part you can reach with grease. But don’t overload the assembly with lubricant, as this can cause problems. Just apply a thin coat to everything.

Step 7: Install New Clips

Now that your assembly is back together, you can reinstall the snap rings or C-clips your universal joint uses to hold everything in place.

Step 8: Reinstall the Driveshaft

Finally, reinstall the driveshaft with the new universal joint, and you are good to go.

Despite how simple this process may seem, getting professional help when replacing your universal joint is the best course of action, as if done incorrectly, you can cause a great deal of damage to your car and put yourself and others in danger.

Is It Time for Your Universal Joint to Get Some Attention?

It is essential that you are aware of the signs of a bad U-joint and take the necessary steps to address the problem without delay. Ignoring the signs of a faulty universal joint isn’t smart, as the complete failure of this component could result in the driveshaft falling out of your car’s undercarriage and causing severe damage and harm to your car, yourself, and other road users. If you act quickly though, you’ll find that your car’s universal joints can be changed without needing to completely overhaul the whole driveshaft.

Whether you need a new U-joint or other car part, Machter has you sorted. With a fantastic range of affordable, quality aftermarket options available, you can find plenty to repair or customise your car for less.