A small but important component of the steering mechanism is the steering universal joint coupling, or simply steering u-joint.
There are two U-joint couplings available in most cars with an intermediate steering shaft.
The top U-junction – the steering column connects to the intermediate shaft, and the lower U-junction intermediate shaft attaches to the steering rack.
See the diagram.
The steering shaft has to rotate at an angle to accommodate the steering tilt and telescope function, as well as for crash safety.
The steering shaft u-joint must transfer the steering force from the handwheel to the steering rack at an angle, without resistance or play.
A faulty u-joint can cause looseness or seize felt within the steering wheel. A vehicle with a bad u-joint steering mechanism is dangerous for driving.
Also, read – What Is Driveshaft? Working Of Driveshaft
Steering u-joint coupling problems
The steering u-joint has four needle bearings full of grease and sealed.
It’s a maintenance-free unit. In many cars, it can last for the lifetime of the vehicle. The most common problem with the steering u-joint is when the grease in one among the needle bearings dries out or when moisture causes corrosion.
In most cases, this problem happens to the lower steering shaft u-joint, as it’s located inside the engine bay.
Symptoms of a bad steering u-joint?
A failed steering u-joint can, cause two forms of problems:
They are, If the u-joint is seized, the steering may become jam or stiffer at certain angles.
There could even be a popping or clunking noise while turning. If the steering u-joint is corroded or worn out, it’ll have some play.
When driving it seems the steering is loose, so you always have to correct it to keep the vehicle driving straight.
A worn-out steering u-joint may cause a rattling noise within the steering when driving on rough roads.
In fact, these symptoms can also be due to other problems in the steering system.
The vehicle is unsafe due to other problems with the steering system or the steering failure.
If your vehicle is showing these symptoms, check your vehicle as soon as possible.
Also, read – How Power Steering Works?
Steering u-joint replacement
A failed steering u-joint coupling must get replaced.
In some cars, it comes as a separate unit, in others it comes alongside the intermediate steering shaft as an assembly.
In a mean car, the replacement of a separate lower steering u-joint costs from $200 to $390.
How easy is it to again replace the steering u-joint?
In most cars, it isn’t very difficult,
although the u-joint is usually seized on the shaft and might be difficult to remove.
In some cars, it is important to mark the steering u-joint position on the steering rack shaft and the intermediate shaft splines, because, as the new u-joint must be positioned in the same way.
In some cars, the u-joint must get replaced with the shaft. it is best to consult the service manual for the vehicle for the right repair procedure.