AST Lowering Springs For BMW 4 420i/428i/430i/420D/425D 03/2014-07/2021, Front 20 , Rear 20

The AST Lowering Springs are precision-engineered components designed to enhance the driving dynamics of your BMW 4 Series (models 420i, 428i, 430i, 420D, 425D) produced between 03/2014 and 07/2021. Manufactured using cold-coiling technology on state-of-the-art Wafios machines, these springs ensure consistent quality and durability. By lowering the vehicle’s center of gravity, they contribute to improved handling and stability without significantly compromising the comfort level provided by the original equipment manufacturer (OEM) springs.

These lowering springs serve as a direct replacement for your vehicle’s OEM springs, specifically tailored to meet the unique suspension requirements of each model. Their progressive spring rate design offers a balanced reduction in ride height—20 mm at the front and 20 mm at the rear—resulting in a sportier stance and enhanced cornering capabilities. The use of premium materials and advanced manufacturing processes guarantees long-lasting performance, supported by a lifetime warranty against breakage.

AST’s commitment to quality is evident in the extensive range of vehicle compatibility, covering over 2500 models from 1966 to the present. This particular set is optimized for the BMW 4 Series, ensuring precise fitment and reliable operation. Additionally, the springs maintain a high level of ride comfort, minimizing the harshness often associated with lowering modifications.

Notes

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

Lowering Specifications

• Front lowering: 20 mm
• Rear lowering: 20 mm
• Progressive spring rate for balanced performance and comfort
• Cold-coiled manufacturing process for enhanced durability

Compatibility

• BMW 4 Series models: 420i, 428i, 430i, 420D, 425D
• Production years: 03/2014 – 07/2021
• Not compatible with four-wheel drive (4WD) variants
• Adjustments for M-sport and Adaptive M-sport suspensions accounted for

In summary, the AST Lowering Springs provide a high-quality, reliable solution for BMW 4 Series owners seeking to improve vehicle dynamics through a modest reduction in ride height. Their design prioritizes both performance and comfort, making them a suitable upgrade for everyday driving as well as spirited performance. Backed by a lifetime warranty, these springs represent a durable and trustworthy investment in your vehicle’s suspension system.

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