AST Lowering Springs For BMW 4 435i/440i/420D/425D 07/2013-10/2020, Front 40 , Rear 40

The AST Lowering Springs for BMW 4 Series models 435i, 440i, 420D, and 425D (07/2013-10/2020) represent a meticulously engineered solution designed to enhance vehicle dynamics by lowering the center of gravity without compromising ride comfort. Manufactured with precision on state-of-the-art Wafios coiling machines, these springs are cold-coiled from premium materials, ensuring consistent quality and durability that meet rigorous automotive standards.

Specifically developed as a direct replacement for the original equipment manufacturer (OEM) springs, the AST Lowering Springs maintain the refined balance between performance and comfort. Their progressive spring rate design allows for improved handling characteristics, reducing body roll and enhancing stability during cornering, while preserving the smooth ride quality expected from OEM components. This makes them ideal for drivers seeking a sportier stance and improved driving dynamics without sacrificing everyday usability.

The set lowers the front and rear suspension by 40mm each, effectively reducing the vehicle’s center of gravity to improve road grip and responsiveness. This lowering height is carefully calibrated to avoid excessive stiffness or discomfort, making these springs suitable for both spirited driving and daily commuting. Additionally, the springs are engineered to maintain compatibility with the vehicle’s existing suspension geometry, ensuring proper alignment and tire wear.

AST’s commitment to quality is reflected in the lifetime warranty offered against spring breakage, providing assurance of long-term reliability and performance. With a broad application range covering over 2500 vehicle models from 1966 to present, these springs have been extensively tested and validated for durability and consistency.

Notes:

• Not suitable for 4WD (four-wheel drive) vehicles.
• Approximately 10mm less lowering effect for vehicles equipped with M-sport suspension.
• Approximately 10mm less lowering effect for vehicles equipped with Adaptive M-sport suspension.

Lowering Specifications

• Front lowering: 40mm
• Rear lowering: 40mm
• Progressive spring rate for balanced comfort and performance
• Cold-coiled on Wafios machines for precise manufacturing
• Designed to reduce center of gravity and improve handling

Compatibility

• BMW 4 Series models: 435i, 440i, 420D, 425D
• Model years: 07/2013 – 10/2020
• Not compatible with four-wheel drive (4WD) vehicles
• Compatible with standard and M-sport suspension (with slight variation in lowering height)
• Direct OEM spring replacement, maintaining suspension geometry

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