Porsche 911 RS A-Arm Ball Joint Set (FI 18). Porsche 911 RS 1974-1989

Porsche 911 RS A-Arm Ball Joint Set (FI 18)
Restore the front suspension precision of your Porsche 911 RS with this replacement ball joint set designed for the FI 18 A-arms. Supplied with the required mounting hardware (hub nut, lock plate, split pin), this set fits the 1974-89 911 RS series and delivers original-spec performance and fitment.
Sold As A Set.
x2 Sets Required Per Car.

Fits:

• 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)

(For Cars Fitted With RS Type Suspension)

What This Product Does:

• The ball joint sits in the lower portion of the front suspension A-arm (wishbone) and provides the pivotal interface between the A-arm and the steering knuckle/hub.
• It allows controlled articulation (up/down movement of A-arm, steering motion) while keeping the hub and suspension geometry correct (camber, toe, caster).
• Because it’s a replacement for the “RS A-arm ball joint”, when worn or loose it can degrade handling, alignment, tire wear, and front-end feel.
• In essence ensures the front suspension remains tight, precise and responsive.

Symptoms Of Wear Or When To Replace:

• Clunking or knocking noises from the front suspension during cornering, over bumps, or when steering — ball joints with internal play can cause these.
  
• Uneven or excessive tyre wear on the inside or outside of the front tyres — worn ball joints allow geometry to drift under load.
  
• Loose or vague steering feel, wandering front end or less precise turn-in — again typically linked to suspension joint play.
  
• Visible rubber boot damage, grease leakage or rust around the ball joint — older 911 RS suspension components may have aged.
  
  

Why Replacement Matters:

• Restores safety & handling precision: On a high-performance classic like the Porsche 911 RS, the front suspension must be tight and accurate — a worn ball joint undermines that.
  
• Maintains correct geometry: Fresh joints help keep camber, toe and caster stable under load — vital for handling balance and tyre life.
  
• Prevents further damage: A failing ball joint can lead to increased stress on tyres, A-arms, bearings and may lead to more costly front-end repairs.

Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

90134104704

The product you are viewing cross references to these numbers