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Ball Joints
This groove nut is used to secure the front lower wishbone (A-arm) ball joint on classic Porsche suspension systems. Manufactured to the exact dimensions and thread specifications of the original Porsche part, it provides reliable clamping strength and precise seating of the ball joint within the control arm.
SET OF 2, each vehicle requires two for a complete front axle set.
Fits:
Porsche 911 1969 - 1989
Porsche 914 1972 - 1976
Diagram ref no 17
This groove nut locks the ball joint securely into the front wishbone, maintaining correct alignment and preventing movement under cornering loads and braking forces. Its machined groove design allows for proper engagement with a locking ring or pin, ensuring long-term stability and safety.
With age, the original groove nut may corrode, lose thread integrity, or deform during removal. Using a worn or non-spec nut can lead to incorrect torque, potential loosening, or suspension play.
Replace when:
• Replacing the front ball joints or wishbone assemblies
• The threads are damaged, corroded, or rounded
• Performing a front suspension rebuild or alignment correction
Installing a fresh groove nut ensures proper torque retention, precise alignment, and dependable suspension performance.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
90134142501
The product you are viewing cross references to these numbers
- Porsche 911 1968-1973 2.2L / 2.4L / 2.7L RS LWB (F)
- Porsche 911 1974-1977 2.7L / 1976-77 3.0 Carrera
- Porsche 911 1978-1983 3.0L / SC
- Porsche 911 1984-1986 3.2L
- Porsche 911 1987-1989 3.2L G50
- Porsche 911 1975-1977 3.0L Turbo (930)
- Porsche 911 1978-1989 3.3L Turbo (930)
- Porsche 914 (1970-1976)
Fits - Left and right.

Fits:
Porsche 911 1969-89
Porsche 914 1972-76
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
BALLJKIT911
The product you are viewing cross references to these numbers
- Porsche 911 1965-1968 2.0L / 912 SWB (F)
- Porsche 911 1968-1973 2.2L / 2.4L / 2.7L RS LWB (F)
- Porsche 911 1974-1977 2.7L / 1976-77 3.0 Carrera
- Porsche 911 1978-1983 3.0L / SC
- Porsche 911 1984-1986 3.2L
- Porsche 911 1987-1989 3.2L G50
- Porsche 911 1975-1977 3.0L Turbo (930)
- Porsche 911 1978-1989 3.3L Turbo (930)
- Porsche 914 (1970-1976)
Fits Left And Right.
Sold Each.
Fits:
Porsche 911 1969>>1989
Porsche 914 1972>>1976
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
90008400402
The product you are viewing cross references to these numbers
- Porsche 911 1965-1968 2.0L / 912 SWB (F)
- Porsche 911 1968-1973 2.2L / 2.4L / 2.7L RS LWB (F)
- Porsche 911 1974-1977 2.7L / 1976-77 3.0 Carrera
- Porsche 911 1978-1983 3.0L / SC
- Porsche 911 1984-1986 3.2L
- Porsche 911 1987-1989 3.2L G50
- Porsche 911 1975-1977 3.0L Turbo (930)
- Porsche 911 1978-1989 3.3L Turbo (930)
- Porsche 914 (1970-1976)
Designed for the front wishbone (control arm) ball joint. Engineered to original Porsche specifications, this nut ensures safe, reliable fastening of the lower ball joint to the suspension arm on Porsche 911 and 914 models.
Sold each. Fits left and right.
Fits:
Porsche 911 1969 - 1989
Porsche 914 1972 - 1976
Diagram ref no 22
The cotter pin nut fastens the lower ball joint to the front suspension arm and secures it with a locking cotter pin through the castle slots. This prevents the nut from rotating loose, maintaining safe steering and suspension geometry during operation.
Over time, nuts can wear, corrode, or lose torque retention due to repeated assembly, age, or exposure to moisture and road debris. A weakened or reused nut may compromise the ball joint’s security, leading to excessive play or unsafe suspension movement.
When to Replace:
• During front suspension rebuilds or ball joint replacement.
• If the original nut is rusted, damaged, or has distorted threads.
• Whenever the cotter pin is replaced, ensuring proper torque and locking function.
Replacing a new cotter pin nut restores factory-level safety, alignment integrity, and reliability in your classic Porsche’s suspension system.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
90008400402
The product you are viewing cross references to these numbers
- Porsche 911 1965-1968 2.0L / 912 SWB (F)
- Porsche 911 1968-1973 2.2L / 2.4L / 2.7L RS LWB (F)
- Porsche 911 1974-1977 2.7L / 1976-77 3.0 Carrera
- Porsche 911 1978-1983 3.0L / SC
- Porsche 911 1984-1986 3.2L
- Porsche 911 1987-1989 3.2L G50
- Porsche 911 1975-1977 3.0L Turbo (930)
- Porsche 911 1978-1989 3.3L Turbo (930)
- Porsche 914 (1970-1976)
Porsche Ball Joints | Design911 Suspension & Steering Components for Precision Handling
Ball joints are crucial pivot points in your Porsche’s suspension system, connecting the control arms to the steering knuckles and allowing smooth, controlled movement of the suspension while steering and driving over uneven surfaces. These components ensure stability, steering precision, and consistent wheel alignment — key for the responsive handling and dynamic balance that define Porsche performance.
At Design911, we supply a comprehensive selection of ball joints and suspension fittings, engineered for strength, accuracy, and long service life. Each component is built from high-grade materials to handle high loads, resist corrosion, and provide consistent performance under pressure. Perfect for routine servicing, suspension restoration, or performance upgrades, our ball joints restore steering precision and ensure your Porsche maintains its legendary road feel.
What Do Ball Joints Do?
Ball joints act as flexible connection points between your Porsche’s control arms and steering knuckles, allowing vertical and rotational movement while maintaining secure wheel alignment.
Core Functions:
• Allow smooth suspension movement and steering rotation.
• Maintain precise wheel alignment for predictable handling.
• Support vehicle weight while absorbing road impact.
• Enable suspension articulation for cornering and braking stability.
• Reduce vibration and improve ride comfort.
Ball joints are essential to maintaining both steering accuracy and suspension balance — ensuring your Porsche feels composed and connected at every speed.
Why Do Ball Joints Fail or Degrade?
Ball joints experience continuous motion, load, and exposure to harsh road conditions, leading to gradual wear or failure over time.
Common Causes of Failure Include:
• Wear of internal bearing surfaces from friction and movement.
• Corrosion or contamination inside the joint housing.
• Cracked or torn dust boots allowing dirt and moisture ingress.
• Excessive load from aggressive driving or poor road surfaces.
• Age-related material fatigue or lubrication loss.
When ball joints fail, symptoms can include clunking noises, uneven tyre wear, vague steering response, and excessive suspension play — all signs that replacement is necessary for safety and performance.
Why Replace or Upgrade Your Porsche Ball Joints?
Replacing worn or damaged ball joints restores handling precision, alignment stability, and steering feedback. Upgraded materials and performance-grade designs also enhance durability and road feel.
Key Benefits:
• Restores precise steering and handling performance.
• Eliminates suspension noise and vibration.
• Improves tyre wear and road stability.
• Available for Porsche 911, 944, 968, Boxster, Cayman, Panamera, and Cayenne
models.
• Made from corrosion-resistant, high-strength materials.
• Ideal for servicing, restoration, or performance tuning.
Design911’s Porsche ball joints deliver exceptional reliability and performance, ensuring your suspension system performs at its peak — whether on the road or the track.
Highlights
• Premium Porsche ball joints and suspension components.
• Precision-engineered for strength and alignment accuracy.
• Designed to reduce vibration and enhance control.
• Corrosion-resistant construction for long service life.
• Fits both classic and modern Porsche models.
• Perfect for suspension servicing, upgrades, or restoration.