Your vehicle’s transmission, or gearbox, is a complex and vital system that ensures seamless gear transitions during your drives. However, when you encounter less-than-smooth gear shifts, you might find yourself asking, “What’s gone wrong with my gearbox?” Quite often, the answer to this question lies in the realm of clutch faults. In this article, we’ll explore the intricacies of clutch-related issues and shed light on the world of gearbox repairs. Whether you’ve experienced hesitant or jerky gear changes, we’re here to guide you towards diagnosing and resolving these problems, helping you get your vehicle back on the road in optimal condition.
There’s something wrong with my car, is it the clutch?
Before we ask if there’s something wrong with your clutch we need to understand what all a traditional clutch assembly is made up of?
- Clutch disc – connects to the transmission.
- The release mechanism (mechanical or hydraulic)
- Cable – connects between clutch pedal and fork.
- Linkage – connects fork to pressure plate.
- Pressure plate – connects to clutch disc
- Flywheel – connects to the engine.
- Pilot Bearing.
- Release or “throw out” bearing.
- Clutch fork – modulates force between pressure plate and clutch via linkage.
Slipping clutch
A slipping clutch is a fault almost everyone talks about but what exactly is it?
Simply put a slipping clutch means that the clutch’s friction material is worn out. The clutch only works through friction, so if there’s too little or no material left to provide friction, then your clutch won’t engage properly. When your clutch slips you will feel that as you release your clutch pedal and accelerate, your car will move slowly while the engine revs higher. Your clutch pedal might also release sooner without having to depress the pedal much.
A slipping clutch could have a lot of potential causes some of which include
- Clutch linkage or cable needs adjustment because the cable is binding or the cable housing is filled with rust.
- Your clutch linkage may be bent, misaligned, or damaged
- Your pressure plate could be weakened or warped.
- The clutch assembly may be contaminated with oil from your engine or transmission oil leaking.
- .Broken motor mounts.
- Riding or overusing the clutch.
Obviously, in all these cases, the clutch would need to be replaced with one with enough friction material as well as diagnosing why the clutch may have prematurely used up its friction material. As Clutches are a wear and tear item in your gearbox there may also be no other reason for the clutch to be replaced other than age or driver abuse.
At RDG we pride ourselves on being able to diagnose what may have been the cause of clutch slippage and offering our customers long term solutions by repairing the cause of the failure as well as the actual fault
While a slipping clutch might not leave you on the side of the road immediately it can cause further damage to the transmission of your vehicle. Your clutch not releasing properly results in your input shaft still turning and cause gear grinding and prevent your car from going into gear.
Eventually, the clutch will fail beyond merely slipping.
Signs of clutch failure
Clutch pedal makes noises when engaging and disengaging
If you can hear a noise when you press the clutch pedal or release it, while the engine is off, then there is a high likelihood that there is a problem with the clutch release mechanism or clutch fork.
The clutch fork is a hydraulic or mechanical device that helps engage and disengage the clutch. You will also hear noises when lubricant dries out and the mechanism wears down. A cable or connection may also cause a squeak or clunk sound.
Clutch pedal shakes or vibrates when you accelerate
A vibrating clutch means the clutch disk is losing grip on the flywheel intermittently. This could have a range of causes including friction material worn out. The material could be burnt or contaminated with oil. The clutch disk hub could be worn, the pressure plate or flywheel could be warped. The pilot bearing may be worn out or damaged or the flywheel itself may be damaged or worn.
Clutch pedal pulsating
When rotating parts wobble or vibrate inside your transmission, you might feel your clutch pedal pulsate. this could be caused by a warped flywheel or a release lever needs to be adjusted. If the pulsation or vibration began after servicing the gearbox, then it’s possible the transmission housing is not aligned with the engine properly.
Clutch pedal stuck on the floor
When a clutch pedal stays stuck on the floor you may have binding problems with the linkage or release bearing. This may be caused by the springs in the linkage being overstretched they might need to be adjusted in this case its also a good idea to check the release bearing and pedal stop.
Clutch pedal feels loose or spongy
A clutch pedal that is loose or spongy is a telltale sign that the release bearing or clutch fork is damaged.Often this is also due to a damaged pressure plate spring in non-hydraulic release mechanisms.
Hydraulic release mechanisms can be more or less problematic and could feel loose or spongy due to air in the hydraulic system, low fluid in the reservoir, leaking hoses or connections, or master cylinder problems.
The clutch pedal is difficult to depress
Every clutch needs some amount of effort to fully depress and engage. If you need to use excessive force to press the clutch pedal in, then you have a problem with the release mechanism. This could be due to a sticking or binding linkage, cable or pivot.
In hydraulic release mechanisms, there may be a blockage or damaged seals in the hydraulic system.
Gearbox grinds or chirps while in neutral
Your vehicle may make a grinding or chirping sound when the gearbox is in the neutral position but the sound goes away when you press the clutch in. This is more than likely the result of a worn input shaft bearing.
Grinding sound while shifting gears
A grinding sound when changing gears is a result of the clutch disc not entirely disengaging. The input shaft then keeps spinning even though the pedal is depressed causing a grinding noise when changing gears
This could be due to many factors with the pressure plate, release mechanism or throw out bearing including clutch cables being stretched or in need of adjustment. It could also be due to issues with the master cylinder or air in the system.
Gearbox won’t go into gear
Clutch problems can also stop you from being able to get into or out of third or reverse gear. This could be due to linkage adjustment problems or a damaged clutch plate.
While hydraulic release systems this could be due to master or slave cylinder issues this is normally also accompanied by a change in the “feel” of the clutch pedal.
At RDG we strive to provide excellent service and quality diagnosing and repairing all manner of gearbox related problems including clutch faults call one of our RDG branches
or simply follow this link to submit a website enquiry one of our helpful service advisors will contact you as soon as possible
Be sure to check out our other informative articles to understand how your gearbox works