Ball Joints

What is a ball joint?

Diagram showing the location of the upper and lower ball joints in a front suspension.

In most vehicles’ front suspensions, the wheels are connected to a steering knuckle or spindle that turns back and forth, allowing the wheels to steer. The knuckle is connected to the rest of the suspension by one or more ball joints.

Much like the joints in our own bodies, ball joints allow the steering knuckle to move in different directions while still being firmly connected to the vehicle. This allows the wheels to turn from side to side, and allows them to move up and down as the suspension compresses or rebounds. 

Your ball joints are considered one of the wearable parts in your suspension, meaning that no matter what, they will eventually wear out and need to be replaced.

When do ball joints need to be replaced?

As their name implies, ball joints contain a ball stud that is trapped in a socket; part of the body of the joint. This allows the ball stud to rotate (allowing the wheels to steer), and pivot (allowing the suspension to move up and down). The whole joint is protected by a rubber boot, which keeps out dirt and water, and seals in lubricant or grease. 

The ball stud is constantly moving as you drive. Because of the tremendous forces being applied to the joint, eventually all this movement wears down the ball stud and the bearings inside the joint. At this point, the ball stud is no longer a tight fit; it has freedom to move around inside the socket. We often refer to this movement as play in the joint. The more worn a ball joint is, the more play there will be. 

Car manufacturers release specifications for ball joint wear limits; how much play is considered acceptable. Once the play or movement in a ball joint exceeds the specified limit, the ball joint is considered worn out and should be replaced.

Why do worn ball joints need to be replaced?

A car with a failed ball joint.

The main reason to replace worn-out ball joints is safety. A ball joint that has too much internal wear can eventually come apart, with the ball stud pulling out of its socket. This can lead to an extremely dangerous situation where one of your wheels becomes partially disconnected from your vehicle. Along with being unsafe, this kind of failure is usually expensive as well, because many other parts are often damaged in the process. 

The excess play in a loose ball joint also allows your wheels to move around more than normal, which can cause excessive or uneven tire wear; a pull to one side; or less predictable handling. 

Symptoms of a worn-out ball joint:

How do you tell if your vehicle needs new ball joints? Here are some warning signs that may indicate one of your ball joints is worn out:

  • You hear a knocking or clunking noise when driving over bumps or uneven pavement. (Possible loose ball joint.)
  • You hear a metallic creaking or squeaking noise when turning the steering from side to side. (Possible seized ball joint.)
  • One or more of your tires is wearing unevenly. 

If you suspect there might be a problem with your ball joints, we’d be happy to provide an expert opinion! An inspection of your steering and suspension components is fairly quick, and doesn’t cost much. 

How can I make my ball joints last longer?

airdrie ball joints
Besides affecting ride and handling, this leaking strut will also accelerate wear on the ball joints.

While the ball joints on every vehicle will probably wear out eventually, there are things that you can do to make them last longer! When replacing your ball joints, it’s important to use the best quality parts available. A ball joint replacement is often labour-intensive, and it wouldn’t make sense to repeat a $500 repair unnecessarily just because you saved $30 on a part! Most of the aftermarket “second line” or “economy” ball joints are cheap for a reason; we’ve seen many that didn’t even last one year. The longest-lasting repair will include an OEM or premium aftermarket ball joint. 

With a good quality ball joint installed, what else can you do to prolong its life? Next, it’s time to take a look at your shocks and struts. Your shocks and struts control the movement of your suspension. They prevent bounce; help absorb impacts; and help to tame motions like body roll when cornering, or “nose dive” when braking. As your shocks and struts wear, this loss of suspension damping speeds up wear on your ball joints. If your shocks and struts are weak; leaking; or have over 150,000 km on them, you should consider replacing them to help increase the life of your other suspension components. 

With our final tips, we’re looking at you truck drivers out there! Many ball joints in trucks are still serviceable, which means they have a grease fitting on them. If you make sure your ball joints are greased at every oil change, they will last much longer. Lastly, remember than anything which increases the weight of your wheel and tire assembly will also speed up ball joint wear. Examples of this would include installing larger tires; installing larger wheels; or installing “LT” series tires on a half-ton truck that came with “P” series tires.

Replacing ball joints in Airdrie:

Pressing in a lower ball joint.

Replacing a ball joint usually involves partially disassembling your vehicle’s suspension. While some ball joints are bolted or riveted on, most of them are pressed in to the control arms or front axle. The round ball joint is forced into a round hole in the control arm, and we use a tool called a ball joint press to remove and install them.

Once the suspension is re-assembled, we usually perform a wheel alignment to make sure everything lines up perfectly. On some vehicles, the ball joint is only available as part of a complete control arm, and an alignment is an absolute must in these cases.

If you’re looking for a skilled team to perform a ball joint replacement for you, we’d be happy to help! We replace hundreds of ball joints every year, and have the experience to know which ball joints will last the longest in your vehicle. After supplying a quality part, with a great quality install, we’ll back the whole repair with the best parts & labour warranty in Airdrie.