Rear Suspension Knuckle - Left for Tesla Model S (2016-2021) | 1042506-00-B

Why This Knuckle Matters for Your Model S

• Model-Specific Fit: Exclusively designed for left rear suspension of Model S (2016–2021), with geometry tailored to match the vehicle’s rear track width (66.9 inches) and suspension travel (5.3 inches).
• Load-Bearing Core: Supports up to 1,800 lbs of static load (per side) – critical for Model S’s battery-heavy rear end – while withstanding dynamic forces during hard acceleration or sudden stops.

Core Functions: Beyond “Just a Metal Bracket”

• Precise Wheel Alignment: Maintains camber (-1.5° ±0.5°) and toe (0° ±0.1°) settings, ensuring even tire wear and stable straight-line tracking.
• Force Distribution: Channels lateral forces (from cornering) and longitudinal forces (from braking) to the suspension links, reducing stress on bushings and ball joints.
• Hub Integration: Houses the rear wheel hub and bearing, providing a rigid mounting point for consistent rotation at speeds up to 155 mph (Model S Plaid).

Signs It’s Time to Replace Your Rear Knuckle

• Uneven Tire Wear: Excessive inner/outer shoulder wear on rear left tire (indicates camber misalignment due to knuckle deformation).
• Vibration at Speed: Shaking in the rear end above 60 mph, often caused by a bent knuckle throwing off wheel balance.
• Clunking Noises: Metallic “clunks” when hitting bumps (signals worn mounting points or cracks in the knuckle).
• Alignment Failures: Inability to maintain proper camber/toe despite repeated adjustments (a sure sign of structural damage).

Engineering That Matches Tesla’s Rigor

• Material: Forged from SAE 1045 high-strength steel (tensile strength: 850 MPa), heat-treated to resist bending under extreme loads – 30% stronger than cast aluminum alternatives.
• Precision Machining: CNC-machined mounting holes and hub bore (tolerance: ±0.02mm) ensure perfect alignment with suspension links and wheel hub.
• Corrosion Resistance: E-coated with a 7-layer protective finish, tested to withstand 1,000 hours of salt spray (equivalent to 10+ years in harsh winter climates).

Professional Installation Guidelines

1. Pre-Installation Prep: Disconnect the 12V battery, remove rear left wheel, brake caliper, and rotor.
2. Removal Steps:
   • Detach stabilizer bar link, upper/lower control arms, and trailing arm from the knuckle.
   • Extract the hub bearing assembly (use a press tool to avoid damaging the new knuckle).
3. Installation:
   • Press in a new hub bearing (recommended: 1043284-00-A) and torque mounting bolts to 85 Nm.
   • Reattach suspension links with torque specs: control arms (120 Nm), trailing arm (150 Nm).
4. Post-Installation: Perform 4-wheel alignment to reset camber/toe, and test drive to verify no vibrations.