The Ultimate Ball Joint Buying Guide
A Guide To Buying Ball Joints
You may not be aware of this component in your vehicle or you least suspect it but in reality ball joints are pivotal suspension system components both literally and figuratively. The suspension articulation is possible only thanks to ball joints and are part of virtually every vehicle on the road today. This guide can help you realize the symptoms of ball joint failure and what you should know before getting new ones so your replacement ball joints work better than original.
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Table Of Contents
1. What Is A Ball Joint?
Ball joints are an important suspension component that connects the control arms to the steering knuckles. The ball joint used in automobiles is similar to the ball and socket joint found in the human body. The ball joints provide a pivot point between suspension and wheels. Ball joints allow independent movement of the suspension relative to the wheel which isolates the vehicle movement from the chassis and helps maintain a smooth and quiet ride.
The ball joint consists of three main sections: the ball and stud, the socket and the boot. The ball is contained in a spherical bearing that is suspended in the socket. The movement of the ball stud relative to the bearing is what provides the ball joint its functionality. The ball is subjected to immense forces and pressures which eventually wears it to the point where the clearance between the bearing surface and ball joint is increased considerably. This renders the ball joint non-functional and requires replacement. The socket must also deal with wear and tear on both the interior and exterior surfaces. It must resist dust, debris and heat from impacting the ball stud and forms the structural part of the entire element. Finally, the boot helps keep the grease inside the ball joint and the contaminants out. If the boot ruptures or wears thin, dust, debris and moisture is allowed to enter into the ball joint housing causing corrosion and rapid wear resulting in failure. The material of the boot is crucial in determining its wear resistance and ultimately how long the ball joint can last.
2. What Should Be My Considerations Before Buying Ball Joints?
Ball joints are one of the most commonly serviced vehicle parts because they endure immense stresses and face a lot of abuse throughout their lifespan. This will put you on the market looking for replacement arts quite often, but choosing between several brands, finding the right type, fit, quality and other factors can make your decision process quite confusing and elaborate. So we have compiled a list of things you need to be aware of when buying replacements for your ball joints.
2.1. Design and Material
The lifespan of a ball joint is a direct result of how well it is built and what materials went into making it. High-quality ball joints use superior materials like sintered and hardened metals to create a robust part that lasts a long time. Most manufacturers showcase their build quality or mention the materials used which can help you understand how well the components are built. The socket and stud must be made of high-grade and high-strength alloy steel. Polyurethane is a good material choice for boots.
The design and material of internal components like the bearing, springs and other fittings are also important. Plastic is cheaper and so many manufacturers get away with using it and it is not always clear to the customer as these components lie inside the ball joint. But if you dig a little deeper you are sure to find the internal product materials. If replacing load-bearing ball joints, it is crucial to find replacements that meet or exceed OE standards. Many aftermarket brands provide OE quality standards at lowered costs. Refer to our top brand’s section to know more about best manufacturers and their product features.
The suspension system design in every vehicle is varied which means the various components are most likely specific to every make and model. The same goes for ball joints as well and finding the right fit for your vehicle is essential for proper functionality. Luckily, PartsAvatar stores components specific to every make, model and year so you can be sure to find products that are designed specifically for your car. Just enter the make, model and year of your vehicle to find relevant products.
2.3. Sealed Vs Serviceable Ball Joints
As the name suggests, sealed ball joints come sealed from the factory and are pre-lubricated with lifetime grease. Whereas greaseable or serviceable ball joints need to be greased regularly to maintain lubrication within the joint. Most modern cars come with sealed ball joints as they require less maintenance and have sufficient service life. Greaseable ball joints can provide longer service life if serviced regularly but failing to do so can result in premature failure.
2.4. High-Resistance Coatings
While steel is one of the sturdiest materials of choice for ball joints, they are also extremely susceptible to corrosion. To counter this many manufacturers apply high-resistance coatings that help keep moisture at bay and reduce corrosion as well as increase wear resistance of the components. Apart from water resistance, ball joints also need to deal with high temperatures that can wear internal parts rapidly and tear boots. The ball joints need to be able to deal with high temperatures along with moisture, debris and other contaminants. Ball joints with special coatings and quality materials are a crucial requirement if the driving conditions are severe.
2.5. Assembly Vs Single Part
As mentioned earlier, the ball joints vary based on mounting, so you need to choose one that matches the type on your car. Unitized ball joint assemblies can only be replaced with control arms. Even some press-in and riveted ball joints cannot be replaced individually and require complete assembly of control arm with ball joint. Also when buying you usually have a choice between going with kits or a single part. This can be decided based on the condition of the rest of your components. But make sure you are getting all necessary parts included for the ball joint replacement like the castle nut, cotter pin, grease fitting (if a serviceable ball joint), etc.
Since all ball joints have pretty much the same construction, the only difference you will notice in price is based on the material and design choice. Not all ball joints are created equally and so you can not expect the same performance from a more economical option than a more expensive one. However, that does not mean that the most expensive option is often the best. The trick is to find the sweet spot between price and quality. One way to dodge this bullet completely is to go with tried and trusted brands like Moog, Mevotech, Delphi, etc. This way you know the quality and performance of the component is going to be well accounted for by its price. Refer to the brand’s section to find the top manufacturers of suspension components.
3. What Type Of Ball Joint Should I Buy For My Vehicle?
3.1. According To Location
There are lower and upper ball joints. Depending on the type of front suspension system in the vehicle, there can be two ball joints. Placed at the lower and upper end of the steering knuckle where the control arm of strut attaches. MacPherson strut only contains a single ball joint at the lower end of the steering knuckle, whereas double wishbone type or multi-link front suspension contains both lower and upper ball joints. Vehicles that have independent rear suspension with rear steering capabilities also contain ball joints in the rear section.
3.2. According To Usage
Based on the location of the ball joint and suspension type of the vehicle, the ball joint can be either load-bearing or a follower type. Load-bearing or loaded ball joints carry the weight of the vehicle and sustain vertical forces during vehicle movement. On the other hand, follower ball joints do not carry or support any loads and are merely there to provide a pivot point and help locate the spindle laterally.
A common example of a follower type ball joint is the lower ball joint in a MacPherson strut and the upper ball joint in double-wishbone type suspension. Loaded ball joints can be found as the lower ball joint in DB suspension. Multi-link suspensions have loaded lower ball joints.
3.3. According To Design
Based on the design of the ball joint, they can be categorized into a sealed or greasable type. Sealed ball joints are pre-lubricated and do not have provisions for added grease. Whereas, greaseable ball joints come with a grease fitting or valve on the socket joint where one can add grease through. Sealed ball joints are found in most modern cars due to their low maintenance requirements. However once worn out they need to be replaced. Greaseable ball joints can last longer with proper maintenance and are often used in heavy-duty applications.
3.4. According To Mounting
Ball joints are attached to the control arms and other components in many different ways: bolt-on, press-in, riveted and unitized connection. Bolt-on type connections are fairly simple and convenient when servicing or replacing but press-in and riveted connections can pose a real issue. For press-in ball joints, you may need special tools or a hydraulic press for removal and riveted joints need to be drilled out. In some cases, removal of the ball joint can compromise the control arm and hence you might need to replace the control arm and ball joint assembly. Unitized design completely integrates the ball joint into the control arm assembly. This replaces the individual ball joints and forms one solid container arm. Many OEM aluminum control arms are unitized. Replacement of such unitized ball joints requires the entire control arm and ball joint assembly be replaced.
4. Which Top Brand Ball Joints Should I Choose?
Since ball joints are such elemental suspension components it is important to source OE grade products from renowned manufacturers. Some of the mentioned brands are not only capable of delivering OE standards but can even surpass the capabilities of OEM replacements providing enhanced strength, versatility, ease of installation, serviceability, etc. The listed features showcase the strengths of each brand product and are there to help you decide the right replacements for your needs.
4.1. Moog Ball Joints
Recent innovations in Moog ball joints have ensured that they have the characteristics and performance that is expected from MOOG. Induction hardening has doubled stud strength and increased durability by a factor of five, which also improves safety. Durability is also enhanced thanks to the new hybrid core carbon fibre bearing which has better friction properties and the increase in radial deflection is reduced by 40% on average. Switching to a new synthetic grease makes the ball joint easier for you to fit as well as delivering optimum smoothness. The zinc flake coating on accessories not only looks better, it also improves corrosion resistance, while the flanged nuts allow higher locking force which boosts safety. Both our press-in and bolted ball joints have new housing coatings which improve their appearance and resistance to corrosion.
- Premium Polychloroprene Sealed Boot w/ Grease-Relief Valve: Stands up to environmental extremes and allows contaminants to be flushed
- Powdered-Metal Gusher Bearing Technology: Provides strength and stability and allows grease to flow through bearing surface for reduced friction and long life
- Full-Ball Hardened Stud w/ Grease Grooves: Promotes longer life and smooth articulation
- One-piece Forged Housing: Provides durability and strength
- Belleville Washer Preload: Ensures tight tolerances
- Greaseable Design: MOOG® ball joints are designed to make lubrication service easier, contributing to longer component life
- Pressed-in Patented Cover Plate Design: Compressed into place, its placement within the housing virtually eliminates excess axial and radial movement of the full-ball stud, securing a solid steering feel for the life of the part
- Easy to install: Precision tolerances for easy installation and steering alignment giving you a perfect fit right out of the box.
- Zinc flake coated and flanged nuts and bolts: Corrosion-resistance and increased locking force
- Metal sealing rings: Optimal sealing
- Carbon fibre reinforced bearing: Less friction and more durable
- Induction hardened stud: More durable and stronger
- Comprehensive coverage: Available for foreign and domestic nameplates
- Moog Problem Solver Ball Joints: Provide long-lasting dependability and performance. Made with a hardened steel stud ball having a full 360-degree range of movement, allowing for consistent stud articulation throughout the life of the part. Grease grooves allow full lubrication between the housing and the ball stud for extended life.
4.2. Mevotech Ball Joints
Mevotech innovates every ball joint component. Their engineers focus on improving part life and ease of installation, employing punishing durability testing to validate every new design. Many of their products offer X-FACTOR DESIGN™ that provide maximum service life and durability to keep your vehicle performing longer. Their LABOR SAVERS™ technology makes your installations much faster, easier while protecting surrounding components, and includes handy Labor Savers accessories in the box.
- Metal design of internal components: Internal metal designs are widely used in the manufacture of Mevotech X Factor ball joints. These designs incorporate highly durable upper and lower metal bearings that surround the ball joint stud and ball, and they include grease fittings to allow for grease and lubrication to be injected into the central area to prolong the life of the ball joint.
- Greaseable: Greaseable ball joints enable the ball joint to be serviced, to flush out old grease and contaminants by injecting new grease during inspection and maintenance routines.
- Knurling: The knurling process on the outer housing of the ball joint cause press-in ball joints to grip and mate with the control arm optimally. Ball joints must be held firmly in place within the control arm in order to function properly. Knurling is an important component of the aftermarket ball joint because it compensates for the wear and deformation of the control arm receptacle.
- Black oxide coating: The black oxide coating provides high resistance to variable corrosion factors such as road debris and adverse road and weather conditions, ensuring prolonged life of the ball joint.
4.3. Delphi Ball Joints
Delphi provides ball joints that have high-strength and smooth operation, made with high-quality forgings and a surface finish machined to micron tolerances. Components are extreme tested to meet OE standards and specifications.
- Precision engineering: Enabling free movement in two planes at the same time, the ball-pin is a critical component. That’s why our ball-pins are manufactured from high-grade steel and machined to micron tolerances. Together with a polyoxymethylene nylon ball-pin seat, they provide optimum durability and smooth joint operation.
- Extensive testing: Delphi ball joints undergo rigorous performance tests including angular stress testing, where the ball is rotated through its angular and rotational travel under load, as well as a pull and push out test, to measure the force required for it to break away from the housing. These important safety tests ensure the ball joint can withstand the same forces as the OE part.
- Cataphoretic coating: Like many of our steering parts, Delphi ball joints feature an environmentally friendly cataphoretic coating for tougher and longer lasting protection from corrosion caused by salt, dirt and water and other contaminants.
- Greater protection: To help prevent damage to the joint’s internal components, all our ball joints come with a special chloroprene rubber cover. The new and improved formula maintains its durability even in extreme temperatures, providing added protection from road dirt or salt and allowing continued free movement of the ball joint for a longer lasting part.
- Longer service intervals: We provide a range of sealed ball joints, that are lubed for life with a high-specification grease, to minimize maintenance requirements. Alongside our precision ball-pin finish and improved rubber boot design, they offer longer ball joint service intervals and better grease retention.
- Extensive dimensional and material analysis to ensure the very best compatibility between the OE and aftermarket part.
- Tested to withstand temperatures below -40ºC and over 120ºC, helping to ensure they perform even under the harshest conditions.
- Parts exposed to 720 hours of salt spray for optimum protection against corrosion.
- Additional cataphoretic coating for greater protection against corrosion and enhanced aesthetics.
4.4. Transit Warehouse Ball Joints
Transit Warehouse TOR or TOUGH. OPTIMAL. RELIABLE series of suspension and steering components stand true to their name. TOR offers a full range of heavy-duty steering and suspension car parts, built for optimal fit and extended service life. Each component is tested throughout the manufacturing process to ensure exceptional performance and reliability.
- Premium quality precision-machined components built to last
- Engineered to withstand extreme weather conditions
- Delivers a smooth, stable ride
- Rigorous testing procedures
- Multi-Axis Vibration: to confirm overall design durability
- Impact Resistance: to verify material’s toughness
- Salt Fogging-to check surface coating corrosion resistance capabilities
- Artificial Ageing: to ensure long-term durability and safety
5. What Are The Symptoms Of A Bad Ball Joint?
Since ball joints take the load of the vehicle while providing constant relative movement between components, they are likely to wear out at some point. Age is an important factor for ball joint failure but other factors also impact the life of the ball joint like failure to or improper greasing and bad driving conditions.
A. Clunking Or Knocking Noise
As the ball joint wears to a certain extent it starts to create noises on operation. These clunking and knocking sounds start to worsen over time as the ball joints deteriorate further. These unusual sounds may be more evident during driving when you go over bumps or steer a turn. You may also hear creaky or squeaky noises when the suspension travels.
B. Uneven Tire Wear
When the ball joints are severely worn out, the clearance within the internal components increases which results in play. The ball joint connects the control arm and spindle and any play or excess clearances can change the wheel alignment which eventually causes uneven tire wear. However, uneven tire wear can be caused due to many reasons and so inspection of the ball joints is necessary. If you notice the inner or outer edge of your tires are wearing out more rapidly than the other then inspect your suspension and ball joints for wear.
C. Excessive Vibrations
With constant use, the ball and spherical bearing in the socket wear out. This wearing induces play in the components which results in noises as well as vibrations. The vibrations can be felt in the steering wheel as you go maneuver potholes and corners. If left unchecked the vibrations will worsen over time and harm other suspensions and steering components.
E. Unsteady Steering Wheel
If the steering wheel tends to go to the right or left, there is a good chance of the ball joints being in a bad condition. The looseness of the steering wheel may become more pronounced when the ball joints are overworking, such as when going over a bump or pothole.
Q) Is It Dangerous To Drive With A Bad Ball Joint?
Ball joints play a role in the steering and suspension of the vehicle. A broken ball joint can cause several issues and risks collisions. If you notice any failing symptoms of ball joints then have the suspension looked at and replace worn ball joints immediately.
Q) What Kind Of Grease To Put In Ball Joints?
The grease used must meet OE standards. The grease used must provide good performance, should be able to sustain high temperatures and last a long time. Heavy duty lithium and marine grease are good options.
Q) Do You Need An Alignment After Replacing Ball Joints?
Replacing the ball joints does not necessarily mean you need to get an alignment. Unless your previous alignment was done with worn ball joints. If you notice unsteady steering feel or uneven tire wear then have your vehicle inspected as you may require an alignment.