Spec 07-10 BMW 335i/135i Stage 1 Clutch Kit *Requires SB53A-2 Flywheel*
The SPEC SB531-2 is a Stage 1 clutch kit for the 2007-2010 BMW 335i and 135i with the twin-turbo N54 and six-speed manual. It is aimed at owners whose factory clutch has started slipping after a tune, or who are tired of the stock dual-mass setup, and who want the smoothest, most OEM-like engagement SPEC offers. SPEC rates it at 430 ft-lb. The key point before you order: this is a non-ratcheting kit that only works with a SPEC billet flywheel, not the factory dual-mass flywheel.
The clutch transfers the N54's torque from the flywheel to the transmission input shaft. SPEC's Stage 1 disc uses a molded, high-performance organic lining, which gives the gentlest engagement and longest life in SPEC's range, close to what a stock clutch feels like. The difference is clamp load and the flywheel system: the -2 suffix kits are built as a matched set with SPEC's SB53A-2 aluminum or SB53S-2 steel billet flywheel, and because they are non-ratcheting they do not use the factory self-adjusting mechanism. N54 cars respond strongly to boost and timing tunes, so a factory clutch that was fine at stock power often slips soon after a flash.
With the car warm, roll into full throttle in fourth from about 2,500 rpm. If the tach climbs faster than road speed as boost builds, the disc is slipping. If the engine pulls cleanly but you hear rattle at idle that disappears with the pedal pressed, the dual-mass flywheel is the likely cause. Our slipping diagnosis guide walks through the load test, and the flare vs. slip guide covers telling slip apart from RPM hang on shifts.
The listing covers 2007-2010 BMW 335i and 135i (N54, manual). SPEC splits this platform by build date. Cars built through January 2009 (E9x 335i, 135i, E60 535i and the N54 Z4 35i) use the SB531-2 with the SB53A-2 aluminum or SB53S-2 steel flywheel. Cars built from February 2009 use the same clutch with the SB53A-3 or SB53S-3 flywheel. SPEC also lists the 2011-2013 335is and the F25 X3 for this kit with a SPEC billet flywheel. Check the production month on the driver door jamb sticker, or send us your year and VIN, so you pair the right flywheel. If you want more holding power, compare the SB532-2 Stage 2 kit.
| Brand | SPEC |
| Part number | SB531-2 |
| Fits | Spec 07-10 BMW 335i/135i Stage 1 Clutch Kit *Requires SB53A-2 Flywheel* |
| Vehicle fitment | BMW 335I/135I (2007-2010) |
| Type | Clutch Kits - Single |
| Condition | New |
| Ships | Same business day (in stock), from the USA |
| Warranty | 1-year |
No. SPEC states the -2 kits are non-ratcheting and require a SPEC billet flywheel: SB53A-2 aluminum or SB53S-2 steel for cars built through January 2009, SB53A-3 or SB53S-3 for cars built from February 2009.
SPEC lists the SB531-2 at 430 ft-lb, with a kit weight of 16 lb.
It depends on the production month, not the model year. Check the build date on the driver door jamb sticker or send us your year and VIN.
SPEC Stage 1 uses a molded organic lining for the smoothest engagement and long life. Stage 2 uses a Kevlar disc with steel backing for higher torque capacity with similar drivability.
SPEC lists the 2011-2013 335is, E60 535i, N54 Z4 35i and F25 X3 for this clutch, each with the correct SPEC billet flywheel for that car.
