Catalog

SACHS 1878008742 DISC CLUTCH

SACHS 1878008742 DISC CLUTCH

Product Specifications

Product quality
OEM Equivalent Grade
starstarstar
Wholesale price USD $49.45
Wholesale price CNY ¥336
bolt MOQ (Minimal order)
20 pcs
local_shipping Production time
30-45 days
package_2 Shipping Weight: —
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SACHS 1878008742
Overview & Operating Principle
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The DISC CLUTCH is the driven disc of the dry single-plate clutch assembly — the friction element interposed between the engine flywheel and the transmission input shaft that transmits engine torque to the drivetrain when clamped between the flywheel face and the pressure plate by the diaphragm spring, and allows the drivetrain to be temporarily disconnected from the engine when the clutch pedal is depressed. The disc consists of a steel centre hub with internal splines that engage the transmission input shaft, allowing the disc to slide axially on the shaft during engagement and disengagement while transmitting torque through the spline mesh; a spring-steel carrier plate welded or riveted to the hub that carries the friction facings and the torsional damper springs; a set of organic or ceramic friction facings bonded or riveted to both faces of the carrier on either side that contact the flywheel and pressure plate surfaces; and a torsional damper assembly integrated into the hub connection — a set of circumferentially arranged coil springs and friction washers between the hub and the carrier plate that absorbs and damps the cyclic torque pulses from the engine's firing order, preventing drivetrain resonance and protecting the transmission input shaft spline from shock loading during engagement. The friction facing material and its thickness determine the disc's torque capacity and service life — organic facings provide smooth, progressive engagement suitable for passenger cars; ceramic or metallic facings provide higher heat resistance and torque capacity for high-performance or commercial applications at the cost of more abrupt engagement characteristics.

This unit — SACHS 1878008742 — is manufactured to OEM-equivalent specifications: disc outer diameter and friction facing inner diameter for the correct clamping area, hub spline count and diameter for the transmission input shaft, torsional damper spring count and rate for the correct resonance damping characteristic, friction facing material and thickness for the OEM torque capacity and service life, and overall disc thickness for correct clutch pedal travel and release bearing engagement geometry are matched to the original part. Supplied as a complete disc assembly ready for installation. Available wholesale from 49.45 USD, MOQ 20 pcs, production lead time 30-45 days.

Clutch discs fail through friction facing wear that reduces the facing thickness until the carrier plate rivets approach the flywheel and pressure plate contact surfaces — the critical wear limit at which immediate replacement is required to prevent rivet scoring of the flywheel and pressure plate; through facing glazing from clutch slip events that generate heat above the facing material's temperature limit, converting the organic binder to a smooth, hard, low-friction film that prevents full torque transmission regardless of remaining thickness; through torsional damper spring fatigue that causes the disc to transmit drivetrain shunting and gearchange judder; and through hub spline fretting corrosion that prevents the disc from sliding freely on the input shaft, causing judder on take-off.

Symptoms & Diagnostics
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Clutch slipping under full throttle acceleration — engine RPM rises without a corresponding increase in vehicle speed, most pronounced in high gears — the friction facing is either worn below its minimum thickness, glazed from previous slip events, or oil-contaminated from a failed rear crankshaft or transmission input shaft seal; confirm by applying full throttle in third gear from 40 km/h — a slipping disc allows the engine to rev freely without vehicle acceleration; measure the remaining facing thickness when the disc is removed.
Clutch judder on take-off — a shuddering vibration felt through the entire drivetrain during initial engagement from rest, worst on uphill starts — the friction facing has developed glazed and unglazed zones from previous slip events, producing differential friction coefficients across the facing; the disc alternately grips and slips across the facing surface during partial engagement; or the torsional damper springs have fractured, eliminating the engagement damping function.
Clutch that drags — gears difficult to select or grinding synchromesh when changing with the pedal fully depressed — the hub spline is corroded or the disc is sticking on the input shaft and not releasing cleanly; or the disc is warped and making partial contact with the flywheel even when the pressure plate is released; a dragging disc causes the input shaft to continue rotating at engine speed when the clutch is pressed, preventing clean gear engagement.
Burning smell when driving in traffic — persistent clutch smell from the footwell or through the ventilation system — the clutch is slipping during normal operation from a facing that is at or near its wear limit; the facing material is generating heat from the continuous slip between its surfaces and the flywheel and pressure plate; the smell is most pronounced after slow traffic where many partial engagements have occurred in a short period.
Rattling or chattering noise at idle that disappears when the clutch pedal is gently depressed — a torsional damper spring has fractured inside the disc hub; the broken spring fragment rattles within its pocket at idle vibration frequency; the rattle disappears when the pedal is pressed because the disc is lifted away from the flywheel and the vibration path changes; confirm by noting the rattle is present only in neutral at idle with the pedal released.
Clutch requiring progressively higher pedal position to engage — the engagement point rising toward the top of the pedal travel over time — the friction facing has worn, reducing disc thickness and requiring the pressure plate to travel further to clamp the disc; as the disc thins, the engagement point rises and the clutch pedal cable or hydraulic system adjustment range becomes insufficient; this progressive change confirms normal facing wear rather than sudden disc failure.
Logistics & Customs
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International HS Code
8483.60
EAEU Customs Code (TN VED)
8483 60 809 0
Typical Net Weight
Country of Manufacture
China
Standard MOQ
20 pcs
Production Lead Time
30-45 days
Always verify the exact 8-digit or 10-digit subheading with your customs broker for the destination country, as tariff schedules and duty rates vary by jurisdiction.
Installation Tips
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  1. Inspect the flywheel face before installing the new disc — examine the full contact surface for heat checking (a fine network of radial cracks), blue or brown heat discolouration, deep scoring grooves from rivet contact, and surface hardening evidenced by a mirror-polished zone; any heat checking, discolouration, or rivet scoring requires flywheel resurfacing or replacement before the new disc is installed; a new disc against a damaged flywheel produces judder from the first engagement.
  2. Check the transmission input shaft spline for corrosion and burring before installing the new disc — slide the new disc onto the input shaft spline and confirm it moves freely by hand through its full axial travel without binding; a spline with corrosion ridges or burred teeth will prevent the new disc from sliding freely during engagement and disengagement, causing judder and preventing clean clutch release; lightly dress any corrosion or burring with a fine file before installation.
  3. Use a clutch alignment tool of the correct spline diameter to centre the disc hub on the crankshaft pilot bearing before tightening the pressure plate — the transmission input shaft must pass through the disc hub spline and engage the pilot bearing simultaneously during installation; a disc that is even 0.5 mm off-centre prevents the input shaft from entering the pilot bearing, requiring the transmission to be lowered and the disc repositioned; never attempt to force the shaft through a misaligned disc hub.
  4. Install the disc with the correct side facing the flywheel — clutch discs are asymmetric; the damper spring hub protrudes further on the gearbox side than the flywheel side on most designs; fitting the disc backwards prevents the pressure plate from clamping correctly and may allow the hub to contact the flywheel casting, causing immediate disc failure; confirm the correct orientation from the disc markings — typically stamped "FLYWHEEL SIDE" or "GETRIEBESEITE" on the respective face.
  5. Do not contaminate the new disc's friction facings with oil, grease, or fingerprints — handle the disc only by the hub and outer carrier edge; even a partial handprint of skin oil on the friction facing surface reduces local friction coefficient and produces take-off judder; if the facing is accidentally contaminated, clean with isopropyl alcohol on a lint-free cloth before installation.
  6. Install the new DISC CLUTCH (SACHS 1878008742) correctly oriented and centred, tighten the pressure plate bolts in a diagonal sequence in three passes to the OEM torque value, install the transmission, adjust the clutch pedal free play or bleed the hydraulic system, start the engine and confirm smooth engagement with no judder, confirm no slip under firm acceleration in third gear, and perform a 500 km bed-in period of moderate use before subjecting the new disc to maximum torque loads.
Tools: clutch alignment tool of correct hub spline diameter, torque wrench for pressure plate bolts, transmission jack, flywheel locking tool, isopropyl alcohol for facing contamination cleaning, fine file for input shaft spline dressing.
Frequently Asked Questions
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Must the pressure plate and release bearing always be replaced simultaneously with the clutch disc?
Yes — replacing all three clutch system components simultaneously is the correct practice without exception. A worn pressure plate with reduced diaphragm spring load will allow the new disc to slip under the same torque that the new disc's facing is rated for; a disc that has been running against a worn pressure plate may appear to have sufficient facing thickness while the full torque capacity of the disc is not being utilised due to reduced clamp load. The release bearing accumulates the same heat cycling and rotational fatigue as the disc — a bearing left from the previous service will produce noise within a short interval that requires a repeat transmission removal. All three components are accessed simultaneously through the same transmission removal; replacing only the disc wastes the labour cost and guarantees at least one further transmission removal within a short period. ok.parts supplies clutch discs individually and as complete three-piece clutch kit sets at wholesale MOQ from 49.45 USD per unit.
What causes clutch judder immediately after fitting a new clutch disc and how is it resolved?
Immediate judder after new disc installation has five common causes: the flywheel face was not inspected or resurfaced and has heat-checked or scored zones that produce differential friction; the new disc was installed backwards; the disc hub is sticking on the input shaft spline from corrosion that was not addressed before installation; the disc facing was oil-contaminated during handling; or the pressure plate diaphragm spring is fatigued and cannot provide uniform clamping force across the full facing area. Diagnosing which cause applies requires removing the transmission again to inspect the installation — check the disc orientation, inspect the flywheel face, attempt to slide the disc on the shaft, and inspect the facing for oil contamination or hot spots. The correct repair addresses the root cause rather than replacing the disc again with the same underlying problem.
How does the OEM-equivalent aftermarket unit compare to the genuine OEM part?
OEM-equivalent units in this catalogue replicate the current OEM design geometry and material specification. Quality is verified against OEM cross-reference data. When ordering in bulk, confirm with our team that the specification matches the latest OEM revision for your application.
Is white-label or custom packaging available for wholesale orders?
Yes. ok.parts works directly with the manufacturing facility and can accommodate neutral white-label packaging or fully branded packaging with your company logo, part numbers, and barcode. Minimum order quantities and lead times for custom packaging may differ from standard stock. Contact the team via the inquiry form to discuss your specific requirements.
Frequently Replaced Together
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PartReason for Combined Replacement
Pressure Plate Assembly (Clutch Cover)
OEM ref. varies by engine torque and transmission		The pressure plate's diaphragm spring provides the clamping force that determines the clutch's torque capacity — a pressure plate whose spring load has reduced from heat cycling cannot clamp the new disc firmly enough to transmit maximum engine torque, producing slip at full throttle with a brand-new disc. Replace the pressure plate simultaneously with every disc replacement; a new disc installed against a worn pressure plate will slip under high torque regardless of the disc's facing thickness.
Release Bearing
OEM ref. varies by transmission type		The release bearing contacts the pressure plate diaphragm spring fingers thousands of times annually and accumulates the same thermal and mechanical fatigue as the disc. A bearing left from the previous service will typically begin producing bearing noise within 20,000–30,000 km of the new disc installation — requiring a repeat transmission removal at the full labour cost. Including the release bearing in every clutch kit replacement eliminates this predictable follow-on repair.
Flywheel
OEM ref. varies by engine		A flywheel that has been subjected to disc slip events will have heat checks, surface hardening zones, or rivet scoring that causes take-off judder with any new disc. Inspect the flywheel at every clutch service — if resurfacing is required and the remaining material would be below the minimum thickness specification after machining, or if heat checking is present, replace the flywheel simultaneously with the clutch kit to restore the complete clutch system to new condition.