H&R Sport Spring Kit – BMW 335xi (E90, N52/N54/N55)

OVERVIEW

H&R Sport Springs for the BMW E90 xDrive sedan are H&R's xDrive-specific spring rate for the all-wheel-drive 3 Series — a different part number from the rear-wheel-drive 335i kit because the extra front-axle hardware changes the corner weight the spring has to control. Replacing the factory coils lowers the car's center of gravity and reduces body roll for sharper handling and a more planted stance, without giving up the all-weather traction that makes an xDrive car worth owning.

The progressive spring rate is increased roughly 10–20% over stock, so the ride stays comfortable day to day and firms up under load. H&R's own fitment chart covers the 325xi, 328xi and 330xi (N52-powered) and the 335xi (N54, then N55 from the final production year).

H&R builds every spring in-house from 54SiCr6 alloy spring steel and shot-peens it to increase service life by more than 200%, so the set resists sag and settling. Each spring is 100% tested before it leaves H&R's ISO 9001-certified plant in Germany, and the range carries TÜV approval.

SPECS

• xDrive-specific spring rate — not interchangeable with H&R's rear-wheel-drive E90 335i kit
• Progressive spring rates, increased approximately 10–20% over stock
• Spring material: 54SiCr6 alloy spring steel, cold-wound
• Shot-peened to increase service life by more than 200%
• Will not settle or sag in service
• Every spring 100% tested before leaving H&R's ISO 9001-certified production facility in Germany
• Quality certification: TÜV and ISO 9001
• Warranty: H&R covers springs for the duration of the original purchaser's ownership of the vehicle the springs are installed on
• Not for E91 Touring (wagon) models

PARTS INCLUDED

• Complete H&R spring set (4 springs) as supplied by H&R Special Springs.
• See the fitting instructions supplied in the box for the full bill of materials.

TECH RESOURCES

Additional Parts Required

• Confirm xDrive drivetrain before ordering. This part number is xDrive-specific. The rear-wheel-drive E90 335i uses a different H&R kit.
• Spring compressor. A spring-only kit requires the struts to be disassembled, which needs a proper coil-spring compressor. Installer-supplied.
• Four-wheel alignment. H&R requires the alignment to be checked and reset any time ride height is changed. Budget for this before ordering.
• Professional installation. H&R states its springs and suspensions should be installed by professional suspension mechanics only. Improper installation voids the H&R warranty.
• Optional: matched sport-valved dampers, since a lowered car holds up better on a damper valved for the shorter spring.

Installation

• H&R Technical Information & Installation Guide (PDF) — spring identification and markings, dead and tender coils, ride-height measurement, bump-stop trim chart by part number, and alignment requirements.
• H&R Warranties & Claims (PDF) — official H&R warranty terms, coverage periods and claim procedure.
• Vehicle-specific fitting instructions are supplied in the box with the spring set. H&R does not publish a separate per-application installation PDF for this part.

Notes

• This is the xDrive (all-wheel-drive) kit only — sedan body style. The rear-wheel-drive E90/E92 335i and the E92/E91 xDrive coupe/wagon variants use different H&R part numbers (50490-4, 50494-2), not this one.
• Vendor listings disagree on the closing model year for the 328xi and 335xi — some retailer catalogs extend coverage through model year 2012, others stop at 2008. Speed Logic uses the conservative reading tied to BMW's own E90 xDrive sedan production run (through MY2011, the last year before the F30 replaced the E90 sedan) and H&R's own note that this kit covers both the N54 and N55-powered 335xi, which places the N55 cars in the final MY2011 model year. Confirm exact fitment with Speed Logic before ordering.

PART NUMBER

• 50494 — H&R Sport Spring set, BMW E90 xDrive Sedan

VEHICLE APPLICATIONS