Mercedes Benz Sprinter 509CDI OM646.984 16V 06-09 Dual Mass Flywheel

Flywheels — Stable Idle, Smooth Take-Off, Clean Power Transfer

A flywheel acts as the mechanical shock absorber between the engine and gearbox. It stabilises idle, smooths clutch engagement and controls vibration under load. When a flywheel is worn, especially a dual-mass flywheel (DMF), it can cause shudder, rattling, harsh gear changes and can quickly destroy a new clutch kit.

What this flywheel restores

• Smoother pull-off with reduced clutch shudder
• Quieter idle with reduced drivetrain rattle
• Stable engagement in traffic, hills and towing
• Cleaner gear changes with reduced drivetrain shock

Important fitment considerations

When to replace your flywheel

• Rattling or knocking noises at idle
• Shudder during pull-off, especially uphill
• Vibration felt through the pedal or cabin
• Harsh engagement or chatter
• Heat spots, cracks, excessive DMF play or worn ring gear teeth

Installation & best practice

• Replace flywheel and clutch kit together
• Replace the CSC during gearbox removal
• Repair rear main seal oil leaks before assembly
• Use new flywheel bolts and torque correctly
• Keep friction surfaces completely oil-free
• Inspect engine and gearbox mountings
• Replace gearbox oil using correct lubricants

Images are illustrative. Confirm fitment by VIN, engine code, gearbox code and OE part number.

FAQs