Driving a manual transmission vehicle can be a lot of fun. It puts the driver in control of the vehicle’s movement in a very visceral way, allowing aggressive drivers to turn their vehicle into a road beast.
However, manual transmission cars project system malfunctions that rarely happen on their automatic counterparts. Clutch failures, like a slipping clutch, strange noises, and wear and tear, are some of these problems. (Automatic transmission uses clutch, though, but they hardly fail).
If you hear a loud knocking, grumbling, or rattling noise when the clutch is pressed down, it shows there’s an underlying clutch issue. There could be several issues that could be causing the noise.
In this article, we’ll discuss what causes clutch noise when pressed down. We’ll also look at the potential ways to fix the problems.
What Causes Clutch Noise When Pressed Down?
Driving manual transmissions requires having a good function engaging and disengaging bearings. The clutch system has other bearings as well, which include the pilot bearings and the throwout bearings. Here are the causes of clutch noise when depressed.
Worn input bearing
The input bearing is a vital clutch component located inside the tranny. If the clutch chatter in neutral when you’re not making use of the clutch, you have a worn input bearing.
Worn throwout bearing
The throwout bearings, also known as release bearing, play an essential role in the optimal function of a clutch system. As you depress the clutch pedal, the release bearing connects to other clutch components via a series of chain reactions.
When you press down the clutch pedal, the release bearing takes charge and controls the contact between the flywheel and the clutch plate.
However, the release bearing is susceptible and can fail over a long period of use. If you hear or feel a noise from the clutch when you release the clutch pedal, chances are you have a failing throwout bearing.
Check and replace it before the vehicle disappoints you and refuses to engage. For detailed signs of a bad throwout bearing, read this article.
Worn pilot bearing
The pilot bearing sits between the engine and the transmission. When the driver depresses a clutch pedal, there are speed variations between the crankshaft and the high gear shaft. The pilot bearing permits these speed variations.
Therefore, a bad pilot-bearing noise intensifies as you depress the clutch pedal. So if you notice foreign noise when you depress the clutch pedal, a worn pilot bearing is likely the culprit. Check and replace it before it damages other system components.
Worn clutch pressure plate
The clutch pressure plates push against the clutch disc, allowing it to make contact with the flywheel when you depress the pedal. This means constant contact, resulting in a high level of friction.
The clutch pressure plates are not built to last the life of a car. I bet you know what that means. They fail under normal operation after some period. A failed or worn clutch can cause several drivability issues.
The most common sign of worn clutch is clutch slippage when accelerating the vehicle. The clutch pedal will behave strangely. You’ll notice a higher clutch pedal, a soft or stiff clutch pedal.
At some point, it’ll start making strange noises when you depress the clutch pedal or clutch rattle at idle. It’s essential to note that the frequency of replacing the clutch plate depends on your driving style and habits.
Clutch pedals in need of lubrication
A clutch pedal is an intermediator between the driver and the clutch system. If the pedal needs lubrication, it’ll produce a squeak or rattling noise when the clutch is pressed or released. Fixing it requires applying grease to the pivot points and the springs.
How Do You Fix A Noisy Clutch?
Due to the complex design of automobiles, problems are bound to happen from time to time. These problems require maintenance to keep the vehicle running as it should. Some problems are minor and need little maintenance to fix. Others are complex and need a certified technician to track and fix the culprit.
One of the common clutch problems that fit this category is clutch noise when pressed down. These annoying noises can require minor or major fixes. It all depends on where the noise is coming from. Now, let’s get our hands dirty.
Step 1: park your car and lift it
Park your vehicle on flat and solid pavement. Lift and support it with a jack stand.
Step 2: locate the clutch slave cylinder
Slide under the vehicle with your mechanic’s work light. Locate the clutch slave cylinder. It should be close to the clutch fork and attached to the transmission.
Step 3: Uninstall the slave cylinder
Remove the two bolts holding the slave cylinder with a wrench. Pull off the slave cylinder from the sitting. Check if it has grease on the end of the pushrod.
Step 4: Remove the rubber boot
With the slave cylinder out of its sitting, pull out the rubber boot and the cylinder rod by prying the base of the boot away. At this point, the piston on the slave cylinder has the tendency of pulling out. To avoid this, compress the end of the cylinder slave against something.
If the cylinder falls off, you’ll have to bleed the clutch again. Well, this is not a big deal since you’re already working on the car.
Step 5: Smooth the pushrod
Wipe off the pushrod using shiny tiny sandpaper. Apply high temp urea grease on the rod. After that, polish everything. Apply tiny grease on the rubber boot. Use your finger to apply some grease to the end of the cup that holds the cylinder to the clutch fork.
Step 6: Reinstall the rubber boot and the slave cylinder
Reinstall the rubber boots on the slave cylinder. This may be challenging with the grease inside. Now, reinstall the slave cylinder to its position. I’ll recommend using one arm to compress the clutch cylinder and another arm to thread the mounting bolts.
Finish the reinstallation by torquing the two bolts that hold the slave cylinder. Torque it to the manufacturer’s specification.
Step 7: Lubricate the throwout bearing
Lubricate the release bearing before lowering the vehicle. Get a nice lubricate and spray it on the throw-out bearing. Locate the opening on the rubber boot on the clutch fork and spray in the lubricant.
Do not spray too much lubricant to avoid causing clutch slippage. I recommend using WD40 for this repair.
Step 8: lower the vehicle
Lower the vehicle and remove the jack stands. Get into the vehicle and depress the clutch pedal. The clutch noise should be gone. If the noise is still there, seek professional help.
The noise is undoubtedly coming from a worn clutch pressure plate or bad release bearing. You’ll have to replace these components. Fixing them requires dropping the transmission. I recommend contacting a certified mechanic to fix this.
Q: Why does my clutch make a noise when I press it?
A clutch pedal should not make any sound when you press it down or release it. So, if you notice any noise on the clutch, either when depressing or releasing the clutch pedal, you have faulty clutch components.
Clutch noises are a sign that the clutch pressure plate or throwout bearing is bad. It could also mean that the clutch joints and springs, or the slave cylinder pushrod need lubrication.
Q: Does a worn clutch make noise?
If you depress your clutch pedal and hear a high-pitched squeaking or squealing noise, you have worn clutches. It could be a worn clutch pressure plate, throwout bearing, or a rusted slave cylinder pushrod.
Track the culprit and fix it as soon as possible. Driving with a noisy clutch can escalate and damage other clutch components.
Q: Is it safe to drive with a noise clutch?
It’s possible to continue driving with a noisy clutch. Sometimes, it’ll not stop you from getting to your destination. However, at some point, you’ll face drivability issues like hard gear shifting, transmission slippage, and slippery clutch.
However, since a noisy clutch signifies an underlying issue, it is unsafe to drive with it. The faulty component may scatter in the middle of a speed lane and cause the clutch to disengage from the engine. If this happens, it can lead to a collision, which can endanger your life and other road users.
Q: How much does it cost to fix clutch noise?
Clutch bearing replacement cost is pretty expensive though the part itself is quite affordable. The labor charge is where you’ll pay a hefty price since the mechanics will drop the whole transmission to access the faulty clutch bearing. This will cost you around $300 to $800 to fix a new clutch. This includes both the part cost and the labor fee.
However, if the strange noise in the clutch system is coming from a rusted slave cylinder pushrod or throw-out bearing, applying lubrication on it will fix it. This should cost you around $30 to $70 for both the service charge and the lubricant.
Now that we have examined what causes clutch noise when pressed down, what if your manual transmission clutch goes away when the clutch is pressed? If a clutch noise goes away when you press the clutch pedal, it is caused by a bad transmission input shaft.
If after diagnoses, you find that the noise is coming from bad internal transmission components, drop the transmission unit and replace it. Inspect all related internal components and replace lousy ones.