Clutch Kit
Buyer's Guide

Buying a clutch kit is one of the few jobs where spending a little more up front genuinely saves you money, because the labor to get in there dwarfs the price of the parts. On most front-drive cars and a lot of trucks, you are pulling the transmission to do this. If you cheap out on a $90 discount-brand kit and it chatters or burns up in 20,000 miles, you pay the labor bill twice. Buy the right kit once.

Three things decide which kit you need: how you drive the car (commute, tow, autocross, drag), how much power the engine makes, and what flywheel you have (single-mass or dual-mass). Get those three right and the brand almost picks itself.

What Is Actually In a Clutch Kit

A "clutch kit" is not just the friction disc. A proper kit includes three or four pieces, and buying them separately almost never saves money:

• Clutch disc (friction plate): the wear item. Splined center rides on the input shaft, friction material on both faces.
• Pressure plate (clutch cover): the spring-loaded assembly that clamps the disc to the flywheel. Its clamp load, in pounds, is what actually determines how much torque the clutch can hold.
• Throwout / release bearing: rides on the input shaft snout and pushes the pressure plate fingers. Cheap kits skip a good one; that is the part that whines six months later.
• Pilot bearing or bushing: supports the input shaft nose in the crank. A $12 part that will strand you if it seizes. Always replace it.
• Alignment tool: plastic on budget kits, worth having. Centers the disc so the transmission slides home.

Kits sold as "with flywheel" or "with concentric slave cylinder (CSC)" cost more but save a second teardown on any car with a hydraulic throwout bearing inside the bellhousing. If your car uses an internal CSC (many GM, Ford, and VW applications), replace it while you are in there. It is not worth pulling the transmission again to change a $60 part.

Friction Materials — The Real Decision

Organic

The stock material on nearly every car sold. Smooth, quiet, forgiving engagement, easy on the flywheel. Holds up to roughly stock-plus torque. If your car is stock or lightly modded and you commute in it, an organic disc is what you want. Do not let a forum talk you into a ceramic puck for a daily driver; you will hate the on-off engagement in traffic.

Kevlar / Aramid

Higher heat tolerance and a longer service life than organic, with engagement that is still streetable. A good middle ground for a tow rig or a mildly built street car. Downside: kevlar wants a proper break-in (500 gentle miles) or it glazes and slips.

Ceramic / Sintered Iron (Puck Style)

This is race material. Very high clamp and heat capacity, holds serious torque, but engagement is abrupt and it chatters cold. Full-face ceramic is livable on a hard street car; 4-puck and 6-puck sprung discs are for track and drag use. If you sit in traffic every day, skip it.

Single-Mass vs Dual-Mass Flywheel

This is the part that surprises people at the parts counter. Many modern manuals (VW/Audi, BMW, a lot of diesels, some GM and Ford trucks) came from the factory with a dual-mass flywheel (DMF). A DMF has springs inside it to soak up drivetrain shock and quiet the gearbox. When it wears out it rattles at idle and can slip.

You have two paths:

• Replace the DMF with a new DMF and a matching organic clutch. Keeps factory smoothness and low noise. Expensive; a quality LuK or Sachs DMF is often the priciest single part in the job.
• Convert to a single-mass flywheel (SMF) with a sprung organic disc. Cheaper, more durable, holds more power, but you will hear more gear rattle at idle because you removed the dampers. Most performance owners do this. Most comfort-focused owners do not.

Do not put a rigid clutch disc on a dual-mass flywheel to save money. Without the sprung hub in either the flywheel or the disc, the driveline has nothing to absorb shock and you get harshness and premature failure.

The Brands Worth Comparing

LuK — The OEM Default

LuK (part of Schaeffler) supplies the factory clutch on a huge share of the cars on the road, so a LuK RepSet kit is very often the exact same part that came out of your car, boxed for the aftermarket. For a stock or near-stock car, this is the safe, correct choice: OEM feel, matched disc and cover, and their RepSet DMF kits include the flywheel where the application needs one. When in doubt for a daily driver, buy LuK.

Browse LuK RepSet clutch kits

Sachs — European OEM-Grade

Sachs is the other big factory supplier, strong on European applications (VW, Audi, BMW, Mercedes). If your car left the factory with a Sachs clutch, buy Sachs again and the engagement will feel exactly like new. Their dual-mass flywheels are well regarded on TDI diesels where a lot of the discount DMFs fail early.

Check Sachs clutch kits

Exedy — Stock Replacement to Stage 2

Exedy is the sweet spot for people who want more than stock without going full race. Their standard replacement kits are excellent value and OE quality (Exedy is factory on a lot of Japanese cars), and they ladder up into Stage 1 (organic, higher clamp) and Stage 2 (sprung ceramic) kits with published torque ratings. If you have a mildly built Honda, Subaru, or Nissan, Exedy is usually the first brand to price out.

Browse Exedy clutch kits

Valeo — Value OEM

Valeo is another genuine OEM supplier and their kits usually undercut LuK and Sachs by a bit while still being a real factory-grade part. Good choice on a budget when you want an OE-style organic clutch and do not need a performance ceramic. Watch the listing for whether the flywheel is included on DMF applications.

Check Valeo clutch kits

ACT and SPEC — Built for Power

When you are past what an OE-replacement kit will hold, ACT and SPEC are the two names to compare. Both let you order a pressure plate by clamp load and a disc by friction material separately, so you can build, for example, a heavy-duty pressure plate with a streetable sprung organic disc, or go full puck for the track. ACT's Heavy Duty and Xtreme pressure plates are a drag/road-race staple. SPEC's stage system (Stage 1 through Stage 5) makes it easy to match to a horsepower target. These are the kits for a turbo build or a swap making real torque; they are overkill and unpleasant on a stock car.

Browse ACT clutch kits

Browse SPEC clutch kits

Do the Flywheel While You Are In There

If you are reusing a single-mass flywheel, get it resurfaced or replace it. Installing a fresh disc against a heat-checked, blue-tinted, or grooved flywheel is the fastest way to make a new clutch chatter and slip. Resurfacing at a machine shop is cheap. If the flywheel is stepped, cracked, or the ring gear is chewed, replace it. On a DMF, do not resurface, replace, because you cannot machine the sprung friction surface true.

Also plan on a new pilot bearing, and inspect the rear main seal and the input shaft seal, since access is never this easy again.

FAQ

How much horsepower can a stock-replacement clutch hold?

Roughly stock crank torque plus a small margin. As a rule of thumb, once you are more than about 15 to 20 percent over stock torque, or you tow heavy, step up to a heavy-duty organic or a Stage 1 kit. Match the pressure plate clamp load to torque, not the friction material alone.

Do I have to break in a new clutch?

Yes, and skipping it ruins ceramic and kevlar discs in particular. Do 300 to 500 miles of easy, varied driving with gentle starts and no hard launches or towing. This lets the friction material bed to the flywheel and pressure plate.

Can I reuse the throwout bearing to save a few dollars?

No. It is inside the bellhousing and it is the part most likely to fail next. It comes in the kit for a reason. Replace it and, on hydraulic systems, replace the concentric slave cylinder too.

Why does my new clutch chatter?

Almost always a glazed or unresurfaced flywheel, oil contamination from a leaking rear main or input seal, or a ceramic disc that was never broken in. Clean assembly and a fresh flywheel surface fix most chatter complaints.