Spec 05-06 Volvo S40 T5 2.5L / 04-07 S60R 2.5L w/ Stock Clutch & Pressure Plate Steel Flywheel

A rattle at idle that goes quiet when you press the clutch, a shudder pulling away, or a clutch job quote that adds a costly dual-mass flywheel to the bill: those are the reasons Volvo S60R, V70R and S40 T5 owners look at a single-mass steel flywheel. SPEC SO60S-O is SPEC's steel flywheel for the turbocharged 2.5-liter five-cylinder, built to run the factory-style clutch and pressure plate. SPEC lists it for the 2004-2007 S60R and V70R; this listing also names the 2005-2006 S40 T5.

What this flywheel does on a 2.5T Volvo

From the factory these cars use a dual-mass flywheel: two masses joined by internal springs that soak up engine pulses before they reach the gearbox. It is smooth when new, but the springs and internal bearing wear, and once the two halves develop play the flywheel knocks, rattles and can judder the clutch. Because it cannot be resurfaced the way a solid flywheel can, it is normally replaced whenever it is worn. SO60S-O swaps it for a single, solid steel flywheel. SPEC lists its weight at 17 lb. The "-O" in the part number matters: SPEC builds this version for the OE clutch design, and its Volvo application chart offers it as the flywheel to use with its non-ratcheting kits made for the OE dual-mass flywheel or any billet flywheel made for the OE clutch.

Expect more gear rattle at idle and a little more driveline noise than a fresh dual-mass unit. In exchange you get a flywheel that can be resurfaced at future clutch jobs and that does not wear out the way a dual-mass does.

Symptoms that point to the flywheel

• Knock or rattle at idle that changes or stops when the clutch pedal is pressed
• Clunk on and off throttle, or when shutting the engine off
• Judder or chatter pulling away even with a fresh clutch disc
• Vibration through the floor or pedal at certain engine speeds
• Heat cracks, blue spots or scoring on the friction face found during a clutch job

None of these set a trouble code. Rule out engine and transmission mounts, a loose heat shield and misfires before blaming the flywheel. Our dual-mass flywheel failure guide covers the checks in detail.

How to confirm before you buy

With the engine idling in neutral, listen near the bellhousing and press the clutch pedal slowly. A rattle that stops or changes with the pedal points at the flywheel or release bearing. Once the gearbox is out, rock the outer mass of the dual-mass flywheel against the inner; excessive free play or a gritty feel means it is done. If the car only slips under boost, the clutch disc is more likely the problem; see the clutch slipping guide. For a side-by-side of the two designs, read dual-mass vs single-mass flywheels.

Fitment

SPEC's catalog lists SO60S-O for the 2004-2007 Volvo S60R and V70R. This listing also covers the 2005-2006 S40 T5 2.5L, which SPEC's own chart does not list, so S40 owners should confirm transmission type and flywheel bolt pattern against the old part, or send us the year and VIN before ordering. Clutch matching is the other key point. SO60S-O is for an OE-type clutch, such as the SPEC Stage 1 SO601 kit or a factory-style replacement. SPEC's Stage 2+ SO603HS calls for SPEC's SO60S billet flywheel, not this one, so do not pair it with the SO603HS Stage 2+ kit. More parts are in our hard parts section.

Install notes

• Replace the flywheel bolts rather than reusing stretched originals, use thread locker as the factory manual directs, and torque in a cross pattern to the factory spec.
• Clean the friction face of any protective coating with brake cleaner before fitting the clutch.
• Center the disc with an alignment tool; the 11-piece clutch alignment kit covers most splines.
• Fit a new release bearing and inspect the slave cylinder and fork while the gearbox is out.
• Bleed the hydraulic clutch with fresh brake fluid of the grade printed on the reservoir cap or in the owner's manual; old, moisture-loaded fluid can make a new clutch drag.
• Bed the clutch in gently for the first few hundred miles before using full boost.

Does this flywheel fit my 2005 S40 T5?

This listing names the 2005-2006 S40 T5, but SPEC's own catalog lists SO60S-O only for the 2004-2007 S60R and V70R. Compare the old flywheel's bolt pattern and transmission type, or send us the year and VIN and we will check before you order.

Which clutch should I use with it?

An OE-type clutch, such as the SPEC SO601 Stage 1 kit or a factory-style replacement clutch and pressure plate. SPEC's Stage 2+ SO603HS needs SPEC's SO60S billet flywheel, which is a different part.

How much does it weigh?

SPEC lists the SO60S-O at 17 lb.

Will a single-mass flywheel make the car louder?

Usually a little. Without the dual-mass springs you may hear more gear rattle at idle and feel more driveline vibration. Most owners accept it in exchange for a flywheel that can be resurfaced at future clutch jobs.

Should I replace the clutch at the same time?

Yes. A new flywheel surface with an old, glazed disc will not bed in properly. Fit a new OE-type clutch, pressure plate and release bearing, and bleed the clutch hydraulics with fresh brake fluid of the grade shown on the reservoir cap.

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