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Details
| Specification | Value |
|---|---|
| Brand | SACHS |
| Outer Diameter [mm] | 430 mm |
OE numbers (3)
About this product
SACHS Flywheel (3421 601 087) is manufactured to OEM tolerances, ensuring a direct-fit replacement that restores your vehicle to factory specification without any modification. Technical specifications — Outer Diameter [mm]: 430 mm, Flywheel Profile: Copper — are verified against the OEM data sheet to guarantee fitment accuracy and performance parity with the original equipment. This part supersedes original equipment references: 20729380, 21184666, 8170617. Matching these numbers confirms a like-for-like replacement with no loss of function. SACHS is a recognised supplier of automotive replacement components to independent workshops and dealer networks across Europe. All parts are sourced from authorised distribution channels and carry full manufacturer traceability — you receive exactly the same component supplied to professional garages and dealer workshops. If fitment or specifications do not match your vehicle, our technical team can help identify the correct alternative — use the vehicle selector or contact us with your VIN for a guaranteed-fit recommendation. Replacing worn components on schedule preserves your vehicle's safety, reliability, and resale value — and aftermarket parts from established brands deliver OEM-equivalent performance at a fraction of the dealer price. Every part is dispatched with tracked delivery and a 14-day money-back guarantee with hassle-free returns.
Flywheel buying guide
Why replace this part?
The flywheel is a precision-balanced steel disc that stores rotational energy to smooth power delivery between firing strokes, provides the ring gear surface for starter motor engagement, and on manual gearbox cars provides the friction surface for the clutch disc. A dual-mass flywheel (DMF) adds a spring-damper mechanism to absorb drivetrain vibration. Worn or heat-cracked flywheels cause clutch slip, rough engagement, and gear rattle.
Signs you need a replacement
- Clutch judder or shudder on engagement
- gear rattle at idle that disappears with clutch depressed (DMF)
- vibration through the gearstick
- starter motor grinding (worn ring gear)
- scoring or hot spots visible on friction face
- poor clutch bite point
When to replace
Always replace the flywheel when replacing the clutch on DMF-equipped vehicles — DMF springs and dampers wear in tandem with the clutch disc. Solid flywheels can be resurfaced if scoring is within limits. Inspect the ring gear for damage.
About SACHS
Sachs, established in 1895 in Schweinfurt, Germany, is a leading manufacturer of drivetrain and suspension components now part of the ZF Group. Sachs specialises in clutch systems, shock absorbers, dual-mass flywheels, and torque converters. As a tier-one OE supplier to manufacturers including BMW, Mercedes-Benz, Volkswagen, and Audi, Sachs components deliver the same quality found in new vehicles. Choosing Sachs ensures reliable drivetrain performance with products engineered to withstand the most demanding driving conditions.
Suitable cars
Vehicle matches are curated from manufacturer data
Confirmed fits based on manufacturer data.No equivalent parts found.
Flywheel SACHS 3421 601 087 — compatible car models
| Manufacturer article number (MPN) | 3421 601 087 |
|---|---|
| OE part numbers | 20729380, 21184666, 8170617 |
Compatibility check
Loading vehicle data…
Please wait while we load vehicle compatibility information.Description and what's included
SACHS 3421601087 . Flywheel Profile: 4. Outer Diameter [mm]: 430 mm
- 1x Flywheel
Shipping, returns, warranty
Free UK delivery on orders over £99.00. Tracked standard shipping.
- Standard delivery: 5–9 business days
- Order before 5pm — ships the next working day
- Free returns within 14 days
- All parts backed by manufacturer warranty
Warranty: 12-month manufacturer warranty on all parts. 14-day money-back guarantee if the part doesn't fit your vehicle.
Frequently Asked Questions
Is this Flywheel compatible with my car?
Use the vehicle selector at the top of the page to check compatibility. Enter your car's make, model, and engine — we'll confirm whether this Flywheel fits. All fitment data is verified through TecDoc.
What specifications does this SACHS Flywheel have?
This SACHS Flywheel has the following specifications: Outer Diameter [mm]: 430 mm; Flywheel Profile: 4. Check the full specifications table above for complete details.
What OE part numbers does this Flywheel replace?
This Flywheel replaces OE part numbers: 20729380, 21184666, 8170617. Cross-reference these numbers with your vehicle's original part number to confirm compatibility.
How much does a Flywheel cost?
This SACHS Flywheel is available for £797.99. Flywheel prices vary depending on brand, specifications, and vehicle compatibility. SACHS parts offer a balance of quality and value, backed by our 14-day money-back guarantee.
How do I know when to replace my Flywheel?
A worn or damaged flywheel causes clutch shudder on take-off, difficulty engaging gears due to a warped mating surface, vibration at idle, or rattling from a dual-mass flywheel that has failed internally.
What tools do I need to replace a Flywheel?
Tools needed: gearbox jack, flywheel locking tool (vehicle-specific), socket set, impact wrench (useful for flywheel bolts), torque wrench. Difficulty: Professional required. Safety warning: Flywheel bolts must be torqued in a star pattern to the manufacturer's specification -- incorrect torque or sequence can cause flywheel detachment at engine speed, which is catastrophic. Always replace dual-mass flywheels with the clutch kit.
Can I use this part as a replacement for OE 20729380?
Yes, this SACHS Flywheel is a direct replacement for OE part number 20729380. It is manufactured to meet or exceed original equipment specifications, ensuring proper fitment and performance. All cross-reference data is verified through TecDoc.
Is the SACHS 3421 601 087 the same as the SACHS 2294 000 070?
No, while both are Flywheel parts, they are different products. The SACHS 3421 601 087 has Outer Diameter [mm]: 430 mm, Flywheel Profile: 4. The SACHS 2294 000 070 may differ in dimensions, fitting position, or material composition. Always verify compatibility with your specific vehicle using our vehicle selector, or contact our customer service team for assistance.
Related categories
Common OE numbers for this part
Common original equipment numbers linked to stocked alternatives.
