4150178
Ball Joint
Vehicle Fitment
| Make | Model | Years | Chassis | Engine | Position |
|---|---|---|---|---|---|
| Autobianchi | A 111 | — | — | — | Front Axle, Lower |
| Fiat | 1100-1900 (101_) | — | — | — | Front Axle, Lower |
| Fiat | 124 (124_) | — | — | — | Front Axle, Lower |
| Fiat | 124 Coupe (124_) | — | — | — | Front Axle, Lower |
| Fiat | 124 Familiare (124_) | — | — | — | Front Axle, Lower |
| Fiat | 124 Spider (124_) | — | — | — | Front Axle, Lower |
| Fiat | 125 (125_) | — | — | — | Front Axle, Lower |
| Fiat | 132 (132_) | — | — | — | Front Axle, Lower |
| Fiat | 1500 Convertible (116_) | — | — | — | Front Axle, Lower |
| Fiat | Argenta (132_) | — | — | — | Front Axle, Lower |
| Fso | 125p | — | — | — | Front Axle, Lower |
| Fso | 125p Estate | — | — | — | Front Axle, Lower |
| Fso | 132p | — | — | — | Front Axle, Lower |
| Fso | Polonez I | — | — | — | Front Axle, Lower |
| Fso | Polonez Ii | — | — | — | Front Axle, Lower |
| Fso | Polonez Iii | — | — | — | Front Axle, Lower |
| Fso | Polonez Iii Saloon | — | — | — | Front Axle, Lower |
| Lancia | Gamma (830_) | — | — | — | Front Axle, Lower |
| Lancia | Gamma Coupe (830_) | — | — | — | Front Axle, Lower |
| Lancia | Scorpion (137_) | — | — | — | Front Axle, Lower |
| Pininfarina | Spidereuropa (P124ds) | — | — | — | Front Axle, Lower |
| Premier | 118 Ne | — | — | — | Front Axle, Lower |
About Ball Joints — function, symptoms & common questions
A ball joint is the spherical bearing that connects a suspension control arm to the steering knuckle — the pivot that lets the front wheel steer left and right while also moving up and down with the suspension. Modern independent front suspensions have one or two ball joints per side; ball joints are also used at some rear-suspension and 4×4 driveline locations.
Also known as: lower ball joint, upper ball joint, suspension ball joint, BJ.
How it works
Steering and suspension articulation
The ball-shaped stud rotates freely inside its socket, allowing the knuckle to swivel for steering input AND tilt vertically as the suspension compresses and extends — both motions through a single compact joint.
Load-bearing vs follower
On a standard control-arm/strut layout the lower ball joint is load-bearing (carries vehicle weight) and the upper joint, if present, is a follower (positions the knuckle but carries no vertical load). On a double-wishbone suspension both joints share the load.
Camber and caster anchoring
The two ball joints (or one ball joint plus the strut bearing) define the steering axis. Joint wear shifts that axis, throwing camber and caster out of spec.
Structure and construction
A hardened steel ball stud retained in a polymer (PTFE/POM) or metal-on-metal bearing inside a forged or pressed steel housing. Sealed with a neoprene/polyurethane boot and pre-greased for life on most modern designs (a handful of heavy-duty designs retain a grease zerk). Press-in or bolt-in mounting depending on control arm design.
Common failure symptoms
- Clunking over bumps. Worn bearing surface allows the ball stud to knock against its socket each time the suspension cycles.
- Steering pull or wander. The steering axis drifts as the worn joint allows the knuckle to shift, pulling the vehicle to one side under acceleration or braking.
- Cupped or feathered tire wear. Camber instability causes the contact patch to skip across the tire, creating uneven wear patches around the circumference.
- Visible play at the wheel. With the wheel off the ground, rocking the tire at the 12 and 6 o'clock positions reveals knocking — a definitive ball joint test.
Common questions about Ball Joints
Should I replace ball joints in pairs?
For load-bearing (lower) joints, yes — both sides see equal duty cycle and the second usually fails soon after the first. Upper (follower) joints can be replaced individually if only one shows wear.
Can I drive with a worn ball joint?
Not safely. Complete failure of a load-bearing ball joint causes the wheel to collapse outward — the vehicle drops onto the suspension and loses steering control. Replace immediately once play is detected.
Is alignment required after replacement?
Yes. Camber and caster are set by ball-joint position; replacement always shifts those values and a rack alignment is mandatory.
How long do ball joints last?
OEM joints typically last 120,000–250,000 km on paved roads. Off-road use, salt corrosion or boot damage shortens life dramatically.
FAQ
What vehicles use OE 4150178?
Form-fit-function tested against the OEM specification. Check the vehicle compatibility table above — it lists every confirmed make, model, year, and position. If your vehicle is not listed, contact us before ordering.
How do I order OE 4150178?
Click Request Quote or email us the OE number with your target quantity and destination. Our team confirms fitment, availability, and lead time within 1 business day. Mix-and-match across part numbers is welcome.