Spec 07-10 BMW 335i/135i Stage 2 Clutch Kit *Requires SB53A-2 Flywheel*

The SPEC SB532-2 is a Stage 2 clutch kit for the N54 twin-turbo BMW 335i and 135i with the six-speed manual, 2007-2010. It is built for the owner who has tuned the car past what the factory clutch holds, is losing rpm to slip in third and fourth, or has a worn dual-mass flywheel that rattles at idle and shudders pulling away, and who wants a firmer clutch that still drives like a street car. It ships same business day from the USA.

What the Stage 2 clutch does in an N54 car

On these cars the clutch sits between the crankshaft flywheel and the six-speed input shaft and has to carry every bit of torque the turbos make. A simple tune adds a lot of low-rpm torque, and that is usually what overwhelms the stock self-adjusting clutch. SPEC's Stage 2 answer is a Kevlar disc with a steel backing, which SPEC describes as giving good drivability, longer life and more torque capacity than stock. SPEC lists the SB532-2 torque rating at 485 and the kit weight at 16 lb.

The "-2" matters. This is SPEC's non-ratcheting version of the kit. There is no self-adjust mechanism to lock or reset during install, and it is meant to bolt to a SPEC billet flywheel, not the factory dual-mass unit. If you want to keep the original flywheel, this is the wrong kit. If you are replacing the dual-mass flywheel anyway, the -2 kit and a billet flywheel are the usual pairing. Need more holding power without moving to a puck disc? The SB533H-2 Stage 2+ uses a multi-friction disc that SPEC rates 15 to 20 percent higher than Stage 2.

Symptoms this kit is meant to fix

• Revs climb with no added speed when boost comes in, worst in the higher gears
• Engagement point creeping up toward the top of the pedal
• Shudder from a stop, or a rattle at idle that goes quiet when you press the pedal, both common with a tired dual-mass flywheel
• Burnt friction smell after a hill start or a few hard pulls
• Grinding into gear, which can also be a hydraulic fault, so check that first

How to confirm the clutch is the problem

Run a load test: fourth gear, around 2,500 rpm, full throttle. If the tach runs ahead of road speed, the clutch is slipping. Then rule out the cheap causes. A slave cylinder that leaks or holds pressure keeps the clutch from clamping fully, and oil from the rear main seal will glaze a new disc in short order. Our slipping diagnosis guide explains how to separate a slipping clutch from other drivetrain faults, and dual-mass flywheel failure symptoms covers the rattle and shudder that point at the flywheel.

Fitment: build date decides the flywheel

Our listing covers the 2007-2010 BMW 335i and 135i N54 manual cars. SPEC splits these cars at the January/February 2009 production change:

• Built through January 2009: SPEC calls for the SB53A-2 aluminum or SB53S-2 steel billet flywheel. This is the SB53A-2 named in our title. We carry the SB53A-2 aluminum flywheel and the SB53S-2 steel flywheel.
• Built from February 2009: SPEC calls for the SB53A-3 or SB53S-3 flywheel instead, such as our SB53A-3 aluminum flywheel.

The build month is on the door jamb label. SPEC also lists this clutch for the 2011-2013 335is, the E60 535i, the N54 Z4 35i and the F25 X3, each with a SPEC billet flywheel. Cars that have been swapped or converted should be checked by part number on the old clutch, or send us your year and VIN and we will confirm before you order.

Install notes

• Install the clutch and the SPEC flywheel together, torque the flywheel bolts to spec with new bolts and clean the friction faces with brake cleaner.
• Center the disc with an alignment tool, such as our 18-piece clutch alignment kit, and tighten the pressure plate bolts evenly in a crisscross pattern.
• On these cars the pilot bearing is carried in the transmission input shaft, so inspect it when the gearbox is out.
• The clutch hydraulics are fed from the brake fluid reservoir. Bleed the slave with fresh fluid of the type marked on the cap, and replace a slave that is wet or sticky.
• Break the clutch in gently with normal stop-and-go driving before any launches or full-throttle shifts.

Can I use the SPEC SB532-2 with my factory dual-mass flywheel?

No. The SB532-2 is SPEC's non-ratcheting kit, and SPEC lists it for use with its billet flywheels only. If you want to keep the factory flywheel, SPEC offers ratcheting kits such as the SB533H instead.

Which flywheel do I need with the SB532-2?

335i and 135i built through January 2009 use the SPEC SB53A-2 aluminum or SB53S-2 steel flywheel. Cars built from February 2009 use the SB53A-3 or SB53S-3. Check the build month on the door jamb or send us your VIN.

How much torque does the SB532-2 hold?

SPEC lists a torque rating of 485 for the SB532-2. If your tune makes more than that, look at the Stage 2+ SB533H-2 or a Stage 3 kit.

What is the difference between SPEC Stage 2 and Stage 2+?

Stage 2 uses a steel-backed Kevlar disc. Stage 2+ uses a multi-friction disc that SPEC says keeps Stage 2 drivability with 15 to 20 percent more torque capacity.

Do I need a pilot bearing for this clutch job?

On the N54 335i and 135i the pilot bearing sits in the transmission input shaft rather than the crankshaft. Inspect it while the transmission is out and replace it if it is rough or loose.

• Transmission Slipping Diagnosis Guide
• Shift Flare vs. Slip: How to Tell Them Apart
• Automatic vs. Manual Transmission Repair Cost