Frequently Asked Questions.

Yes! All ACT clutch assemblies are computer spin balanced to within .25 oz-in to guarantee help smooth operation across the entire RPM range. For comparison, stock production clutches are typically balanced to within .50 oz-in. Lower is definitely better!

ACT pressure plates are specifically designed to handle high torque applications. With ACT's durable design, expect an increase in pedal effort between 15-40% (Heavy Duty) and 50-80% (Xtreme), depending on the application. Clutches developed with less pedal effort often result in a lack of longevity, torque capacity and/or engagement quality.

For organic street discs, we recommend breaking in the clutch for 300-500 miles with mild engagement, such as stop-and-go city driving prior to racing or spirited driving. ACT race discs usually only require a few hard slips to lap in the surfaces prior to normal driving or racing. Do not overheat the clutch during the break in period, as this can result in friction surfaces fusing together, hot spots, and friction surface glazing.

In some situations, rebuilds or repairs may be possible (see warranty), after inspection of the clutch assembly. Please contact our technical department for further information. Because of special modifications, we do not recommend servicing by a general clutch rebuilder.

The weight of the ACT clutch assembly will usually be the same as a stock OEM clutch assembly.

The ACT clutch system is designed to work with both stock and good quality aftermarket flywheels. Inferior aftermarket flywheels may have trouble with warpage or high wear. When replacing a flywheel, be sure that the new flywheel meets the same specifications, such as proper step, ring gear tooth count, flywheel thickness, ring gear offset, etc. If the ACT clutch is designated as part of a conversion kit, then it must be used with only the corresponding ACT flywheel.

The flywheel step determines the proper working range of the pressure plate and is extremely crucial for the clutch to work properly. The step is the distance between the friction surface and the pressure plate mounting point on the flywheel. Depending on the make and model of the car it can either be an UP step or DOWN step and sometimes the flywheel will be flat (zero step). Check the manufacturer's specifications about the proper flywheel step for the application.

Yes, ACT XACT flywheels can be resurfaced just like a stock flywheel and there is no special process other than using a flywheel grinder in good condition to remove as little material as possible for full cleanup (no more than 0.040” / 1.02mm may be removed). Make 100% sure that the proper flywheel step is maintained as this will affect the clutch function if incorrect.

ACT's race discs are very aggressive and provide no-nonsense performance response. As a result, the engagement is harsh. Taking off from a stop can cause judder and/or an uncomfortable noise. These characteristics have no effect on the performance on the clutch or the drive line components. This type of disc should only be used in a professional race setting and never on the street. ACT always recommends using an organic disc on the street because it offers a smoother engagement and a longer lasting performance value for everyday drivers.

The majority of new discs measure .312-.315” (7.93 – 8.00mm) thick – fully worn is .275” (7.00mm) or below. A few applications (mostly Audi and BMW) start out at .332 - .335” (8.43 – 8.50mm). These are to be replaced when below .295” (7.50mm). It’s best to measure with a micrometer. Puck discs are measured as-is, where organic street discs are correctly measured by fully compressing the engagement cushion (marcel) between the linings. If the lining rivets on either side of the disc have made contact with the flywheel or pressure plate face, the disc much be replaced. Note: Using a disc that is thicker or thinner than the working range the pressure plate is designed for will have varying, and often very poor, results.

The stock indication is 90% accurate, however it's not the actual live stock position. Please contact us to be 100% sure of our stock position.

There are many manufacturers and designs for clutches. We do our best to use the best parts for your application. Check the part numbers and compare what is listed on our application chart for your vehicle. If the components fit properly without modification, chances are you have the right parts. If it appears something needs to be modified to make it work, stop and contact us.

ACT discs can be purchased separately. However, because of the labor involved in changing a clutch, we do recommend replacing the entire clutch at the same time.

ACT only offers components for manual transmissions. Automatics use a completely different setup all together and nothing is interchangeable.

All ACT products are designed with longevity in mind; however, clutch life will greatly depend on the vehicle, your type of driving and output of the engine. For example, a vehicle in heavy stop-and-go traffic will have a shorter clutch life than the same vehicle that is driven on the open highway.

It is important to match the proper ACT clutch system with the vehicle and its intended use! Knowing what characteristics wanted in a clutch and the power capability of the engine is important.

All ACT kits contain a pressure plate and clutch disc. Release bearings, alignment tools and pilot bearings (where applicable) are included in selected kits. Kit component parts are listed on each kit page and in the application chart.

All ACT clutch assemblies are designed to be a direct bolt in replacement for the stock clutch assembly. Pedal height adjustments are sometimes necessary depending on application. If adjustments for a specific application are required, a supplemental technical bulletin will be provided.

Yes, if your vehicle is equipped with a pilot bearing or bushing, it is recommended to replace and properly lube the pilot bearing/bushing when changing the clutch.

Yes! The alignment dowel pins properly locate the pressure plate to the flywheel. Without these pins, severe vibration and engine damage can result. The alignment dowel pins should always be replaced if they are damaged, broken off, or missing from the flywheel.

When using stock clutch bolts, refer to the manufacturer's service manual for proper torque specifications. New bolts are highly recommended. ACT suggests using SAE Grade 8 or Metric Grade 10.9 fasteners and increasing the torque specifications (5/16 or 8mm bolts can be tightened to at least 30 ft. lbs. / 47 Nm). Lock washers or thread locking compound is also recommended. Proper torque is critical for safety. Take the time to obtain the correct pressure plate assembly and flywheel bolt torque specifications and tighten the bolts correctly using a high quality torque wrench. Also be sure to tighten bolts using a diametrical star pattern as indicated in the vehicle service manual. Never use air tools for installing or removing clutch bolts!

If having clutch trouble prior to installing an ACT clutch, find the cause of the problem before installing the new clutch. There are many problems caused by worn or faulty linkage, hydraulic system issues, oil contamination and misalignment or transmission damage. Please see ACT's installation instructions and the vehicle service manual.

A smooth, flat flywheel surface is essential for proper clutch operation. Flywheels are subject to heat, scoring and warping during use. If upon careful inspection there are signs of scoring, heat damage or warpage the flywheel should be resurfaced or replaced to assure proper clutch performance. Resurfacing should be done on a flywheel grinding machine only. Refer to the factory service manual or ACT information for resurfacing specifications (Flat, Step, Etc.). WARNING: IF THE FLYWHEEL SHOWS ANY SIGNS OF CRACKING, REPLACE IT! Never roughen the flywheel clutch surface with sanding as this reduces clutch life. The surfaces are designed to rub against each other (abrasion), not tear into each other (causing abrasion). If you have any further questions, please call 661-940-7555 and ask for the tech department.

Improper clutch release caused by faulty linkage and/or improper adjustment, pilot bearing damage, insufficient lubrication of release mechanism or input shaft splines. It takes a remarkably small amount of drag on the input shaft to make life difficult for transmission syncros.

Improper clutch adjustment, lack of free play or work out disc.

Inadequate clutch release can be caused by many problems. Possible causes may be as follows: 1) Clutch linkage not properly adjusted or reset. 2) Flywheel not resurfaced before new clutch installed. 3) Flywheel surfaced improperly, such as incorrect flywheel step. 4) Flywheel machined too thin or not manufactured to stock (O-E-M) specifications. 5) Lack of lubrication on linkage or release bearing collar. 6) Linkage worn or damaged. 7) Hydraulics defective, leaking or air in the system. Just one bubble is enough! 8) Cable stretched or damaged. 9) Pilot bushing binding due to improper bellhousing alignment, bellhousing damaged or loose. 10) Clutch disc installed improperly. 11) Clutch disc hub rubbing against flywheel bolts. 12) Clutch disc binding on input shaft or damaged splines. 13) Input shaft bent causing clutch disc runout. 14) Pressure plate assembly and/or clutch disc bent or damaged. 15) Clutch disc is too thick or has excessive marcel (too much cushion between the friction linings). 16) Pressure plate has defective or damaged torque drive straps. 17) Damaged, worn, or improperly installed pilot bushing/bearing. 18) Oil or grease contamination on clutch facings. 19) Damaged or worn release bearing collar.

Judder is when the car shudders (chatters) as the clutch is being engaged. Possible cause may be as follows: 1) Flywheel has excessive run-out. 2) Flywheel was not resurfaced or improperly resurfaced before the new clutch was installed. 3) Damaged or excessively worn CV joints. 4) Bad U-Joints in drive shaft or U-Joints misaligned. 5) Excessive backlash in differential. 6) Excessive driveline angle. 7) Bad leaf springs, bushings or mounts. 8) The use of an aggressive clutch disc designed for racing. 9) Defective pressure plate and/or disc. 10) Disc has inadequate marcel (not enough cushion between the friction linings). 11) Oil or grease contamination on clutch facings. 12) Worn or damaged clutch linkage. 13) Bent pressure plate assembly and/or disc. 14) Improperly tuned engine. 15) Worn or damaged engine mounts or transmission mounts. My new release bearing appears to be off center on the bearing retainer and wobbles. Is it defective? No. Vehicles that have a self-centering bearing may appear to be off center or improperly manufactured. During first use after assembly, the bearing will align and center itself as required.