Exedy 04-17 Subaru WRX STI EJ255/EJ257 2.5L Twin-Organic Clutch Kit

A built or big-turbo Subaru WRX STI will overpower the factory single-disc clutch long before the 6-speed gives up, and the usual result is slip in the upper gears, chatter, or a pedal that feels different every week. The Exedy FM022SDF is a Hyper Series twin-plate clutch with organic friction for the 2004-2017 STI with the EJ257 2.5L turbo and 6-speed manual. It is the twin plate for owners who want much more holding power but still want the engagement of an organic disc in traffic.

What the twin organic clutch does in an STI

The STI 6-speed uses a pull-type clutch release: the release bearing pulls the diaphragm fingers back toward the transmission instead of pushing them in. This kit keeps that factory actuation. Exedy says its Hyper Series clutches bolt in and use the factory actuation system without modification.

Inside the kit, two organic friction discs share the load with a floating intermediate plate between them, and the center disc is sprung to soak up driveline shock. Because the clamping force works on two discs, the clutch holds far more torque than a single disc of the same diameter without needing a much heavier pedal; Exedy says most Hyper Series kits have similar or lighter pedal effort than stock depending on application. Every Hyper Series kit includes a lightweight one-piece forged chromoly flywheel, and Exedy states that flywheel is required. The factory flywheel is not reused.

Symptoms that point to a clutch upgrade

• RPM rising without acceleration in fourth, fifth or sixth under boost
• Slip that shows up only after the car is heat-soaked or after a few hard pulls
• Chatter or shudder on takeoff with a worn or glazed single disc
• A burnt smell after launches, or a disc that is near its minimum thickness at inspection
• Planned power that is beyond what the stock or a Stage 1 single disc can hold

How to confirm the clutch is the problem

Rule out the hydraulics and release side first: check the clutch fluid, bleed the system and confirm the pedal returns fully. Then do a high-gear slip test from low rpm at full throttle and watch whether rpm climbs faster than road speed. If the clutch slips, the stock disc has reached its limit or is worn. Our manual vs automatic repair cost guide explains what a clutch job involves in labor so you can plan to do it once with the right parts.

Fitment

The listing is for the 2004-2017 Subaru WRX STI EJ255/EJ257 2.5L. In practice that means the STI with the EJ257 turbo and the 6-speed manual; the EJ255 mention reflects that the same twin kit is also cataloged for 2007-2009 Legacy GT spec.B 6-speed cars. It does not fit 5-speed WRX models. Match the 6-speed transmission and send us the year and VIN if you have any doubt. You can compare other STI options on our Exedy Hyper Twin cerametallic STI kit page if you are racing more than driving.

Install notes

• Hyper Series kits do not include the release bearing or pilot bearing. Exedy sells a Hyper Series Accessory Kit (FJAK100 is the one listed with this clutch) that supplies them; order it or new OE bearings at the same time.
• Use the included chromoly flywheel. Exedy says it can be machined later, but the correct flywheel step must be kept.
• Center both discs with an alignment tool such as our 11-piece universal clutch alignment kit, keep the discs and intermediate plate in the order shown, and tighten the cover bolts evenly in a star pattern to factory spec.
• Bleed the clutch hydraulics until the pedal is firm, then check that the clutch fully releases before driving.
• Expect a rattle with the pedal pressed. Exedy says the floating pressure plate and intermediate plate design will rattle when the clutch is disengaged; it is normal.

If you prefer a single disc, compare the Clutch Masters FX400 STI kit.

Does it fit a 5-speed WRX?

No. This twin plate is for the WRX STI with the EJ257 and 6-speed manual (and is also cataloged for the 2007-2009 Legacy GT spec.B 6-speed). Non-STI 5-speed WRX cars use a different clutch.

Can I keep my stock flywheel?

No. Exedy Hyper Series kits include a lightweight forged chromoly flywheel and Exedy states it is required. The factory flywheel is not used with this clutch.

Are the release and pilot bearings included?

No. Exedy does not include release or pilot bearings with Hyper Series clutches. Order the Hyper Series Accessory Kit or new OE bearings at the same time so the job is done once.

Is the rattle with the pedal down normal?

Yes. Exedy says its twin and triple plate kits use a free-floating pressure plate and intermediate plate that rattle when the clutch is disengaged.

Will the pedal be heavier than stock?

Exedy says most Hyper Series kits have similar or lighter pedal effort than stock depending on the application.

Can the clutch be rebuilt later?

Yes. Exedy sells each Hyper Series component separately, so worn discs can be replaced without buying a whole new kit. If the flywheel is machined, the correct step must be retained.

• Automatic vs. Manual Transmission Repair Cost: What to Actually Expect