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SKU: BCB-ALY0017K | UPC: 700424680955
Cobb 15-21 Subaru WRX & STI/2018 Type RA Alloy Front Lower Control Arm (Complete) Offset Caster
The Cobb Alloy Front Lower Control Arm with offset caster fits 2015-2021 Subaru WRX, STI and 2018 STI Type RA models. This complete assembly replaces factory steel arms with lightweight aluminum for sharper steering and better alignment under load. Gain 1.5 degrees of additional caster to enhance straight-line stability and cornering grip.
Key Features
- Billet 6061-T6 Aluminum: Cuts unsprung weight by over 40% versus OEM steel arms for quicker suspension response and improved ride quality.
- 1.5° Caster Offset: Boosts dynamic caster for consistent camber control during hard cornering and high-speed stability.
- Complete Assembly: Includes Moog ball joints, Energy Suspension HyperSTREET II polyurethane bushings and all hardware for direct bolt-on replacement.
- Enhanced Geometry: Maintains optimal suspension kinematics on lowered or modified vehicles without alignment compromises.
- Anodized Finish: Resists corrosion and wear for long-term durability in harsh driving conditions.
Product Notes
- Wheel alignment required after installation to dial in caster gains.
- Compatible with OEM or aftermarket sway bars and coilovers.
- Ships as single arm; order pair for both sides.
Installation Notes
- Professional installation recommended.
- Bolt-on using factory mounting points; no cutting or welding needed.
- Torque bushings and ball joint to Subaru service manual specs.
This Part Fits
| Year | Make | Model | Submodel |
|---|---|---|---|
| 2015-2021 | Subaru | Impreza | WRX |
| 2015-2021 | Subaru | WRX STI | |
| 2018 | Subaru | WRX STI | Type RA |
Why Choose Cobb?
- Decades of Subaru-specific engineering from street to rally stages.
- Track-proven components tested on VA-chassis WRX and STI platforms.
- Precision CNC-machined in the USA for exact fit and function.
Frequently Asked Questions
-
Q: Will this fit my 2017 WRX with coilovers?
A: Yes, designed for 2015-2021 WRX, STI and 2018 Type RA; works with stock or lowered setups up to 2 inches drop. -
Q: What bushings and ball joints are used?
A: Equipped with Energy Suspension HyperSTREET II durometer-matched polyurethane bushings and heavy-duty Moog ball joints for smooth operation. -
Q: What is the warranty coverage?
A: Backed by Cobb's 2-year limited warranty against manufacturing defects when installed properly.
Shipping & Handling
- Method: UPS Ground or USPS Priority
- Availability: In stock - ships same or next business day
- Packaging: Protective foam-lined box, 17" x 11" x 5"
- Weight: 6.1 lbs
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