Universal joints, also known as U-joints are one of the most important parts in any drive train. They connect the two ends of axles together and transmit torque between them while allowing them to rotate at different speeds or directions. U-joints were invented in the year 1905 by Mr. Charles Constantine with his model name “Constantinesco”.
U-joints are located on the underside of your vehicle’s driveshaft. This important part of the drive train transfers power from the transmission to the rear axle, ultimately turning your wheels.
The most common type of U-joints is known as cv or constant velocity joints which resemble a cross shape, where it looks like two yokes (the name for one half of a U-joint) and it is what the driveshaft connects to.
The other kind of U-joints are known as an “open” type, they resemble a capital letter A and consist of only one yoke on each end of the drive shaft. These joints transfer power from the transmission to the axle by a rotating pin.
U-joints, allow the differential to turn faster than the engine, while still allowing it to move at a slower pace than wheel rotation for better traction and control.
If damaged, U-joints can cause a host of problems. They are built to be sturdy but can get bent or knocked out of alignment. They also wear over time, which is normal. The wear process in the U-joints is known as fretting, where the surface of the yoke develops fine cracks. These fine cracks can expand leading to misalignment and wear and eventually complete failure of the U-joint.
How much does it cost to replace a universal joint?
The cost of universal joints is typically $20-$80 per piece. This means that having a mechanic replace them will cost $100-$300 plus labor depending on if it was an easy replacement or not (for example, access to the underside of the vehicle).
The amount replacing U Joint also depends on how many U joints you need to replace. Usually, it is $175 for 4×4 wheel drives trucks per axle, $250 for 6×6 wheel drives trucks per axle, $125-$200 dollars for 2-wheel drives per axle cars. This price also varies depending on the brand and material of the components.
The total cost for replacing U joints can be $200-$700 for most vehicles per axle (4×4, 6×6 and 2-wheel drives) and $1,000 -$2,500 for most trucks.
6 Common Symptoms of a Failing U Joint
If you think you have a bad U joint, the most common symptoms of a failing U joint are:
1.) Squeaking Noise
If you hear a squeaking noise coming from the driveshaft or under your car, this is probably a bad U joint. When the U joint fails and starts to wear out, it will cause a squeaking noise while you are going down the road. If it is bad, you might even hear a grinding or popping noise when you turn.
2.) Clunking Noise
Another common symptom is clunking or popping noises when you are turning. This mainly happens when the joint starts to wear out and becomes loose, causing it to move around. If this gets worse, it will likely lead to other problems with your vehicle that can end up being very costly.
Also read: P0327 Knock Sensor 1 Circuit low Input (Bank 2 or Single Sensor)
3.) Vibration while moving quickly
When U joints are bad, they tend to make your vehicle vibrate while you are driving over 45 miles per hour. This is because the U joint becomes loose and starts to move around when it fails.
4.) Transmission Fluid Leaking
You might notice that you are losing transmission fluid when the U joint starts to go bad. This is because the seal between it and your vehicle’s driveshaft fails, causing fluid to leak out. If this happens you should get your vehicle looked at right away, since it can also cause other more costly problems with your transmission system if not addressed quickly.
Also Read: What Will Happen if You Overfill Transmission Fluid
5.) Unable to Move Vehicle
When the U joint goes bad, it can cause the driveshaft to become misaligned which will result in your vehicle not moving. This is one of the most serious problems that you could experience if your U joints are failing.
6.) Driveshaft dislocated
Lastly, your vehicle’s driveshaft can also dislocate if the U joints wear out and detach from the undercarriage of your car. If this happens, the driveshaft will no longer be connected to your vehicle and you most likely won’t be able to drive anywhere until it is repaired.
Are U-joints easy to replace?
When it comes to replacing U joints, they are very easy to replace. It can be done by a home mechanic with relatively little experience and not the best tools in the world. Most mechanics that do automotive repair will have no problem replacing U Joints on almost any car or truck.
The only time it might get complicated is if your car has an independent suspension system because you might need to jack up part of your car’s undercarriage to access the driveshaft. This is a more difficult process than a standard driveshaft which most cars use with a solid axle design, but it is still pretty straightforward when compared to other types of repair jobs.
In conclusion, U joints can be a pretty large expense if they need to be replaced. If your driveshaft is making a lot of noise or you think that something might be going on with your U joint, it would be a good idea to have it looked at as soon as possible.
If the joint is bad, it will either wear out completely, which will cause vibrations and other problems to develop in your vehicle’s drive train, or the U Joint may end up breaking apart while you are driving (which could cause serious damage). These things can quickly become very costly if not addressed right away. “You should budget an average cost of $200 – $500 per axle for replacement parts and labor.”