Bilstein B12 Pro-Kit Suspension Kit 46-223678 – BMW 335i / 340i / 435i / 440i (F3x)

OVERVIEW

The BILSTEIN B12 (Pro-Kit) is a matched, fixed-height performance suspension package: a complete set of BILSTEIN Performance dampers paired with application-specific EIBACH Pro-Kit progressive-rate lowering springs. Depending on application the kit lowers the car between 24 and 40 mm.

This suspension kit provides a dramatic increase in the vehicle’s performance handling characteristics and is designed for drivers wanting precision control and superb driver comfort, while seeking out more curves to conquer. BILSTEIN calls the matched damper-and-spring approach its Professional Cornering System (PCS): precise response, excellent performance, predictable control, lowering up to 40 mm, and a lower, action-ready looking vehicle.

The B12 (Pro-Kit) is the product of two companies at the top of their industries: the shock absorber experts at BILSTEIN and the spring professionals at EIBACH. BILSTEIN dampers use monotube gas pressure technology and are made in Germany.

SPECS

• BILSTEIN damper family: B12 (Pro-Kit) — fixed-height performance kit
• Internal design: monotube gas pressure
• Not ride-height adjustable — the B12 (Pro-Kit) is a fixed-height kit; BILSTEIN’s threaded, height-adjustable kits are the B14 and B16 lines
• Springs: EIBACH Pro-Kit, application-specific progressive rate
• Position: front and rear (complete four-corner kit)
• Finish: dampers yellow / springs dark gray
• Lowering: up to 40 mm
• Made in Germany
• Warranty: BILSTEIN Limited Lifetime Warranty (as published by BILSTEIN for this part number)

PARTS INCLUDED

• Four BILSTEIN B12 (Pro-Kit) performance dampers — front and rear
• Four EIBACH Pro-Kit application-specific progressive-rate lowering springs — front and rear
• Complete kit as supplied by BILSTEIN; see the installation instructions for the full bill of materials.

TECH RESOURCES

Additional Parts Required

• Four-wheel alignment. A full four-wheel alignment is required after installation — camber, caster and toe all change when ride height changes.
• Professional installation. BILSTEIN requires that the work be carried out by a qualified technician on a chassis hoist with proper spring-compression equipment; improper installation risks serious injury.
• Check EDC. Confirm whether your car is equipped with Electronic Damping Control before ordering — EDC cars require different mounting components and BILSTEIN lists separate part numbers for them.
• Installer-supplied: chassis hoist or jack stands, spring compressor, and a torque wrench — do not use impact tools on suspension fasteners.

Installation

• BILSTEIN shock absorber and spring-carrying strut mounting instructions (E4-WM5-Y217A00, DE/EN, PDF)
• BILSTEIN suspension strut removal and installation instructions (E4-WM5-Y519A00, DE/EN, PDF)

Notes

• BILSTEIN lists this kit for the BMW 335i 2012–2015, 340i 2016–2018, 435i 2014–2016 and 440i 2017–2020. BILSTEIN publishes generic mounting instructions for this kit rather than a vehicle-specific guide; use them alongside the BMW factory repair procedure for your chassis.

PART NUMBER

• 46-223678 — BILSTEIN B12 (Pro-Kit) suspension kit, BMW F3X 335i / 340i / 435i / 440i

VEHICLE APPLICATIONS