U-Joint Replacement
What is a universal joint?
A universal joint is a joint that is bolted or welded onto a shaft, and allows that shaft to rotate, even when bending. In rear wheel drive and four-wheel drive vehicles, they allow the suspension to travel without breaking the drive shaft.
How does the universal joint work?
By attaching a four-way hinge between two shafts, the two shafts can move independently of one another, in all directions, and the power from one of the shaft can be transferred to the other end of the shaft, even while the shaft is bent. This allows the drive shaft, and some axles, to connect two components that are not in fixed positions relative to each other.
A defective U joint will cause a vibration that can be felt throughout the vehicle. This may be especially bad during acceleration.
What are the symptoms related to a bad universal joint?
Commonly, vibrations that increase with vehicle speed, and a rapid chirping noise are very evident when a universal joint (U-joint) fails. The chirping and vibration may change intensity as the vehicle passes over bumps in the road. As the problem progresses, the drive shaft may make a loud clunk anytime the vehicle is put into reverse or drive. Vibrations, and wobbling will eventually lead to leaky seals on the transmission tail shaft, or transfer case. When the U-joint has reached total failure, it may bind and break, which can allow the drive shaft to fall off the vehicle while driving.
Can I drive with a universal joint problem?
It is not recommended to drive with a failing universal joint. Every time the universal joint squeaks, is a chance it can bind and break. If driving the vehicle must be done, slow speeds and light acceleration are recommended. The universal joint should not be left unattended and in operation for any extended period of time, as failure will occur, and damage to the vehicle is possible.
How often do universal joints need to be replaced?
Universal joints can have a lengthy service life if properly maintained, and 100,000 miles is not at all unreasonable to expect. U-joints to fail prematurely, most commonly as a result of vehicle abuse, collisions, lack of maintenance, and dry-rot of the rubber lip seal.
How are universal joint issues diagnosed?
When a U-joint is making noise, the entire driveline must be inspected to determine the noisy joint. The noisy universal joint will feel loose compared to the others, and may even have visible movement. The transmission or transfer case seal nearest the U-joint may also be leaking, and the carrier bearing, if equipped, may be worn.
How is a universal joint replaced?
The faulty universal joint is replaced as an individual component, or by replacing the entire drive shaft. Vehicles with non-serviceable universal joints will require driveshaft replacement. Serviceable u-joints require removing retaining clips, and sliding one side of the joint out of the yokes at a time. The new universal joint slips in, and is help by retaining clips. If the transmission of transfer case seal requires replacement, the drive shaft is easily removed, and installed.
RepairPal Recommendations for universal joint issues
We recommend using OEM quality or better when selecting universal joints. These parts tend to be inexpensive, and are vital to the smooth operation of your vehicle. Purchasing low quality universal joints may lead to repeating this repair.
What to look out for when dealing with universal joint issues
If the universal joint binds and breaks, when it falls from the transmission, transmission fluid will be lost quickly from the tail shaft, and the engine will rev higher than expected. This can result in transmission damage, and can be prevented by repairing the issue soon after it is noticed.