Your car’s clutch will wear out over time. Unfortunately, there’s no getting around it, as it’s one of your car’s many consumable components. The clutch works using friction, connecting the moving parts that transfer the power from your engine to the gearbox that drives your wheels.
With its continuing connection and disconnection of moving parts, the clutch is vulnerable to wear during everyday operation. Fortunately, the plates that make those connections are made from highly resilient materials, offering years of flawless operation before finally requiring replacing.
A standard clutch should deliver around 60k miles of driving before it needs replacing, depending on the type of driving and the driver’s driving style.
Check out our clutch kit cost, quote, and information page for more information about clutch replacement costs. Our expert Fixter mechanics guide you through typical costs for different makes and models, how long the work can take, and what additional factors can play a part in the replacement. We’ll also provide you with instant quotes for your car.
What’s in a clutch kit?
There are generally three main components in a clutch kit. With some, you might find an alignment tool included to make the process a little easier, and in others, maybe even a pilot bearing.
- Clutch disc
- Pressure plate
- Release bearing
- Optional: alignment tool
If you’re buying a performance clutch kit, there’s a chance you could find a lightweight flywheel included in your bundle.
1. Clutch disc
The clutch disc—often called a clutch plate or friction disc—provides the grip between the flywheel and clutch plates, delivering the power from the engine to the transmission (the gearbox).
To provide the necessary grip required to transmit all the power between the rotating discs, each side of the clutch disc is constructed from robust friction-supported materials designed for long life and exceptional performance. The clutch disc is fixed to the pressure plate, which, in turn, is mounted to the flywheel.
There are additional clutch plate springs mounted on the inner hub of the clutch plate. They act as extra dampeners to soften each connection and gear change as the clutch disc connects with the flywheel.
At the centre of the clutch disc sits its splined hub. This splined hub transfers the movement of the flywheel to the gearbox through the transmission shaft, but only when the clutch plate is firmly held between the flywheel and the pressure plate.
2. Clutch pressure plate
The pressure plate’s key component is its spring. The spring operates the movement of the pressure plate, forcing the clutch plate against the flywheel when the clutch pedal is released. The pressure plate and spring are housed in a cover. The cover is fixed to the flywheel leaving each component free to move independently.
The pressure plate spring isn’t the typical metal coil we usually associate with springs. Instead, it’s a round plate known as a diaphragm spring. These circular steel discs have a hole in the centre (necessary for the transmission shaft) and are radially slotted, leaving ‘release fingers’ that delivers the required movement and spring action.
3. Release bearing
The clutch release bearing (also known as the throwout bearing) sits against the pressure plate diaphragm spring. When the clutch pedal is depressed, it pushes the centre of the spring inwards, releasing the outer edge and the clutch disc from the flywheel.
The release bearing’s job is to absorb the rotary motion of the diaphragm spring and the pressure plate while disconnecting the disc from the flywheel.
4. Alignment tool
Each clutch kit is different, operating with its manufacturer’s splined hub at the centre of the clutch plate. Manufacturers often include an alignment tool with the matching number and arrangement of splines to the hub to ensure exact alignment. This ensures that the alignment between the pilot bearing (located in the flywheel) and the clutch plate is precise.
How does a clutch kit work?
It’s pretty tricky to visualise from a text-only description, but the basics go like this:
- When you depress your clutch pedal, it pushes the release bearing into the diaphragm spring of the pressure plate.
- As the centre of the spring moves towards the clutch plate and flywheel, the outer edge moves further away, releasing the contact of the pressure plate and clutch plate.
- Without the necessary force sandwiching the clutch disc between the pressure plate and flywheel, the clutch plate is free to slow down and stop spinning. The driver can now safely change gears by releasing the engine power from the clutch plate and transmission shaft.
As we said, it’s not easy to visualise the exact mechanics if you’re not an engineer or a mechanic. So, to make life easier for you—and clutches simpler to understand—why not watch this great cutaway video showing exactly how a clutch kit works. Good old YouTube!
Why can changing a clutch kit be so costly?
Given clutch kits aren’t horrifically expensive to buy (check out some manufacturer’s clutch kit prices and how we determined our average price of £235), it’s often the time-consuming process to change your clutch that adds cost to the job.
Replacing a clutch kit costs between £300 and £700, with the average coming in at £475. You might need to add the price of a flywheel in there too, and a gearbox oil flush to keep everything silky-smooth. However, it’s down to it being at least half a day’s work to access a clutch for removal that explains away those often-high costs.
Many vehicles will need the engine lifted or dropped to crack the engine and gearbox apart, as that’s where the clutch sits. Separating those major components is a pretty meaty job and why replacing your clutch kit is such a labour-intensive operation.
Performance clutch kits
If your vehicle operates under less than typical conditions—for example, if it tows heavy loads, trailers, is a sports model or an off-road vehicle—then there’s a chance it could need a little extra help. Performance kits come under many guises, so selecting the correct option for your make and model and the job it undertakes is essential.
In such performance clutch kits, you’ll often find that the clutch plate is made of carbon or ceramic material, delivering the level of friction required of high-performance engines.
Of course, high-performance vehicles don’t just operate on bigger engines but their weight to power ratios. With that in mind, some performance clutch kits will include the addition of lightweight aluminium flywheels instead of the traditional heavy-duty steel part.