Reliable and powerful:Clutches for Passenger Cars by SACHS.

Hill starts, endless traffic jams and winding roads – clutches for passenger cars are subject to a wide variety of demands every day. SACHS clutches in OE quality get car drivers into gear easily. They ensure great convenience and are particularly reliable. SACHS clutches for passenger cars are also convincing due to their long service life.

Clutch kit for passenger cars

SACHS clutch kit for passenger cars

Today, the service life of individual clutch components is almost identical. The SACHS clutch kit for passenger cars takes this into account by providing all relevant components that are required for clutch replacement. These are usually the clutch pressure plate, clutch disk and clutch release bearing.

The kit’s scope of supply includes a special grease for assembly that guarantees perfect functioning after the replacement. With the SACHS clutch kit for passenger cars, clutch replacements can be performed safely, effectively and swiftly.

SACHS clutch kits are available in various combinations. In addition to the modern XTend clutch pressure plate, the most advanced kit also includes a dual-mass flywheel (DMF).Besides the clutch kit with DMF and XTend, there are additional combinations, for example with concentric slave cylinder CSC.These are also available from SACHS.

XTend clutch pressure plate for passenger cars

SACHS XTend clutch pressure plate for passenger cars

Even the highest-quality and most durable car clutch is subject to operational wear and tear. This is where the technology of the XTend clutch pressure plate made by SACHS comes in: It provides automatic wear compensation. How it works: The XTend clutch pressure plate for passenger cars separates facing wear from the movement of the diaphragm spring. The compensation mechanism constantly registers reduction in the lining and compensates for the clearance by reliably turning an adjustment ring. This keeps the clutch from being vulnerable to extreme temperatures, soiling and aging. Furthermore, the pedal-force conditions remain constant over the entire service life. At the same time, the service life is extended, since the facing can continue to be worn. Another advantage of XTend is in its design: The installation space required axially in the clutch system with operational wear is reduced through the use of XTend.

Pilot bearing for passenger cars

SACHS pilot bearing for passenger cars

The pilot bearing, also referred to as the guide bearing, is predominantly responsible for the functioning of the passenger-car clutch. As a ball bearing, it guides the transmission input shaft and is thus predominantly responsible for the functioning of the clutch in the passenger car. If wear results in an angular offset, the shaft is no longer properly supported, which may lead to clutch defects. SACHS offers passenger-car pilot bearings for all common vehicle models. When replacing the clutch, the pilot bearing should always be inspected and, if required, replaced as well.

Differential before clutch

Differential before clutch

DBC stands for differential before clutch and means that a transmission input shaft is mounted in front of the dual-mass flywheel (DMF). This requires what is known as a drive plate, a transfer plate that ensures that the transmission input shaft has enough space. There are many advantages of a high-quality SACHS DBC: It provides outstanding vibration damping over the entire speed range and effectively reduces noise. Moreover, it is largely unaffected by extreme temperatures, soiling or wear and features high durability.

DBC is used in particular in vehicles with an engine installed longitudinally and front-wheel drive. It is available with dual-mass flywheels (DMF), a DMF module and practical clutch kits that include all the components for a clutch replacement. The installation of a DBC is easy using the included special tool: SACHS provides the relevant installation instructions.

Damage evaluation

Clutch slips

Clutch slip may have various causes. For detailed information on the damage evaluation, please go to the useful tip: “Clutch slips.”

Clutch does not disengage

If the clutch does not disengage, the problem is not necessarily the clutch itself. Frequently, the cause can be found in the clutch release system, the pilot bearing or installation errors. For detailed information on the damage evaluation, please go to the useful tip: “Clutch does not disengage.”

Clutch grabs

Clutch grab is not necessarily caused by a defective clutch. For detailed information on the damage evaluation, please go to the useful tip: “Clutch grabs.”

Clutch noise

Clutch noise such as whistling or clunking is not always an indication of a defective clutch. Whistling noises may also be caused by off-center contact of the clutch release bearing, off-center transmission input shafts or defective pilot bearings.

Clunking noises may be due to load alterations if clutch disks are furnished with preliminary dampers. These noises do not impair the function or service life of the clutch disk.

Incorrectly installed parts or installation of the clutch disk in an incorrect installation position can also lead to noise generation.

Therefore, it is recommended to consider the following questions:

  • Was the correct part installed?
  • Was it assembled in the correct installation position?
  • Are pilot bearings installed and OK?

For additional information on clutch noise and expert evaluations, please go to the useful tip: “Clutch noise.”

Problems in the clutch environment

Problems caused by components in the clutch environment mostly indicate that important points were forgotten or overlooked during clutch replacement. Therefore, it is necessary to inspect the following parts for function reliability and/or wear:

  • Pilot bearing
  • Guide tube
  • Clutch release system

FAQ about clutches

What is the function of the clutch?

The clutch has a wide range of functions in the vehicle. It connects the mass to the engine without jerks, interrupts the power transmission between engine and transmission when the vehicle stops and interrupts the power flow to change the transmission ratio. Additionally, it provides vibration damping and overload protection.

What are the components of a clutch?

A complete clutch consists of flywheel or dual-mass flywheel (DMF), clutch disk, clutch pressure plate and clutch release bearing.

Where is the clutch located in the vehicle?

The clutch is located between the engine and transmission.

How does the XTend clutch pressure plate for passenger cars work?

XTend clutch pressure plate for passenger cars

The XTend clutch pressure plate made by SACHS provides automatic wear compensation by separating facing wear from the movement of the diaphragm spring.

Facing wear changes the installation position of the diaphragm spring as the pressure plate moves towards the flywheel. As a result, the leaf springs are shifted axially and move into a steeper position; the contact pressure and pedal forces increase. Every time the clutch is engaged, the housing stop registers the facing wear and lifts the retaining spring off the adjusting rings by the amount of the wear path. The wedge-shaped slide (pulled by its extension spring) moves into the newly formed gap and locks the retaining spring in the raised position. When disengaging the clutch, the adjusting ring pair is axially relieved. Due to the prestress of the adjusting ring spring, the lower adjusting ring rotates until the upper ring is in contact with the retaining spring again. The diaphragm spring has returned to its original position and the facing wear has been compensated.

What aspects have to be considered when replacing an XTend clutch pressure plate for passenger cars?

Always use a special tool for replacing the XTend clutch.

During disassembly, keep in mind that the housing stop is lifted off the clutch housing. If it is not released, the adjusting mechanism is triggered during disassembly so that it cannot be reset anymore. Since the facing wear is mechanically memorized in the clutch pressure plate, it is only possible to reinstall the unit that has already been used (clutch pressure plate and disk). If a new clutch disk is required, the clutch pressure plate must be replaced as well. Since the compensation mechanism of the clutch pressure plate that has already been used cannot be reset, the clutch would not disengage.

Why should I install the XTend clutch with the aid of a pre-tensioning tool?

To ensure that the readjustment mechanism works properly and is not wedged. That way, stress-free installation is guaranteed.

What aspects have to be considered when assembling the clutch?

The screws that secure the clutch pressure plate to the flywheel have to be tightened and/or loosened alternating crosswise. Assembly brackets and/or transport safety devices have to be removed after the installation. Also, the clutch facings should be free from dust, dirt, oil and/or grease. Check the correct centering position of the transmission bell housing relative to the engine housing in order to avoid misalignment.

What should be considered when installing a clutch disk?

Prior to the installation of the clutch disk, a lateral run-out tester should be used to ensure that the lateral run-out of the clutch disk does not exceed 0.5 millimeters. Find detailed information on the lateral run-out tester in the useful tip: “Clutch disk check”.

What factors may adversely impact the service life of a clutch?

The service life of a clutch depends on factors including the applied stress and driving style. The clutch is adversely affected by setting off in a gear that is too high or at a speed that is too high, or by stopping the vehicle on a hill with the clutch slipping, for example. Furthermore, decelerating via clutch by shifting down or overloading the vehicle and/or the trailer should be avoided. Also avoid setting off on extreme inclines in rapid succession and frequent maneuvering.

When does a clutch separate perfectly?

In order to examine the separating characteristics, disengage the clutch with the engine idling. Wait for three seconds. Afterwards, the reverse gear should engage without noise (important: immediate engagement of the reverse gear always results in shifting noise).

When does a clutch slip?

Before the test, you should take the vehicle for a short drive, operating the clutch several times in order to heat up the clutch to operating temperature. Afterwards, firmly apply the parking brake, engage the highest gear and accelerate in the disengaged state until an engine speed of approx. 2,000 rpm is reached. Maintain the speed and quickly engage the clutch.

If the engine stalls, the clutch's transmission capacity is OK. To avoid overload, only repeat this procedure once.

Further information