Symptoms of a bad transmission

14 minute read Published on Jan 22, 2024 by BrokerLink Communications

Close up of a car technician hands holding some car's parts

The transmission is a vital component of your vehicle, essential for its movement and overall performance. It is the powerhouse that dictates the efficiency and smoothness of your car’s movement, but what happens when it starts to fail? Recognizing the early warning signs of a bad transmission can differentiate between manageable repairs and a complete transmission overhaul.

In this blog, we’ll explore the most common symptoms of faulty transmission, from odd noises and slipping gears to unusual smells and delayed response times.

What is a car’s transmission?

A car’s transmission is a complex mechanical system that plays a critical role in the vehicle’s operation. It’s designed to transfer power from the engine to the drive axle in the most efficient way possible, effectively controlling the speed and torque.

There are several types of transmissions, including manual, automatic, semi-automatic, and continuously variable transmissions (CVTs). Each type operates differently, but all serve the same primary function. In a manual transmission, the driver selects the appropriate gear using a gear stick and clutch pedal. In an automatic transmission, this process is handled by the transmission system itself, which uses a complex set of hydraulics and sensors to determine the optimal gear change.

The main job of a transmission is to ensure that the right amount of power goes to your wheels to drive at a given speed. It does this by shifting gears in a very similar way to what you see on a multi-speed bicycle. A transmission changes the gear ratio between the engine and the wheels. In a lower gear, your engine runs faster relative to the speed of the wheels; in a higher gear, it’s the opposite. This allows the car to accelerate effectively and drive at high speeds while keeping the engine’s RPM within a suitable range.

How long does a transmission generally last?

The lifespan of a vehicle’s transmission can vary widely depending on several factors, including the type of transmission, the make and model of the vehicle, driving habits, and maintenance practices.

Keep reading to learn how long a well-maintained transmission can last:

Manual transmission

On average, manual transmissions can last between 100,000 to 120,000 miles or even more. Some may last the lifetime of the vehicle. Manual transmissions tend to be simpler in design compared to automatics, which can contribute to their longevity.

Automatic transmission

Automatic transmissions typically last around 100,000 to 150,000 miles or more. However, their lifespan can be on the lower end of this range if they are subjected to harsh driving conditions or if maintenance is neglected.

Continuously variable transmission (CVT)

CVTs, which are becoming more common in modern vehicles, may have a slightly shorter lifespan compared to traditional automatics, often around 100,000 miles. However, with advancements in technology and proper maintenance, newer models may exceed this range.

Signs of transmission problems you should never ignore

Recognizing the early signs of transmission problems, such as strange noises, slipping gears, or transmission fluid leaks, can save you from costly repairs and ensure the safety and reliability of your vehicle.

Problems with the transmission can lead to poor fuel economy, difficulty in shifting gears, and even complete vehicle breakdown. You can help prevent transmission issues with regular transmission maintenance. Regular maintenance is crucial for the longevity and performance of the vehicle.

Understanding the various transmission problem signs in depth can help you identify and address them early. Here are some key signs of transmission issues that you should never ignore:

Strange sounds

Unusual sounds from your transmission are often the first sign of trouble. When in neutral, if you hear noises like humming, buzzing, or whining, it might indicate issues with the transmission’s internal parts, such as worn bearings or gear teeth.

Similarly, if these sounds occur while shifting gears, it could be due to worn or damaged components. It’s important to note the specific conditions under which these sounds occur, as this can help a mechanic diagnose the problem more accurately.

Transmission fluid leak

Transmission fluid is crucial for lubricating and cooling the transmission’s internal components. If you notice a leak under your car typically a bright red, clear liquid with a slightly sweet smell, it’s a clear sign of trouble. Leaks can lead to low fluid levels, which can cause overheating and damage to the transmission. Regularly checking the ground where you park your car can help you spot leaks early.

Slipping transmission gears

A properly functioning transmission should stay in the selected gear until a change is initiated. If an automatic transmission slips in and out of gear on its own, it’s a sign of wear and tear or a more serious issue like a faulty solenoid, worn clutch plates, or other internal damage. This not only reduces your vehicle’s performance but can also be a significant safety risk.

Delayed shifting

This issue is particularly noticeable when shifting from park to drive or reverse. If there’s a noticeable delay before the car starts moving or if you feel a significant jerk when the transmission engages, it could indicate a problem with the transmission fluid, valve body, or other internal components.

Rough shifts

An automatic transmission should shift gears smoothly. If you experience rough, abrupt, or jarring gear shifts, it might indicate a problem with the transmission’s bands, clutches, solenoids, or possibly a need for fluid replacement. It’s often accompanied by an increase in RPM before the gear finally engages.

Check engine light

Modern vehicles are equipped with sensors and computers that monitor the transmission’s performance. If your transmission warning light or check engine light illuminates, it’s important to take it seriously. These lights can activate for various reasons, including sensor failures, overheating, or mechanical problems. While it might not always be a transmission issue, it’s important to diagnose it as soon as possible.

Burning smell

A burning smell emanating from your vehicle could be due to overheating transmission fluid. This can occur due to overuse, towing heavy loads, or fluid degradation. Overheated fluid loses its ability to lubricate and cool the transmission, leading to increased friction and wear.

Changes in transmission fluid colour or smell

New transmission fluid is typically bright red and has a slightly sweet smell. Over time, with wear and heat, the fluid can become contaminated and degrade, turning dark brown or black, and may develop a burnt odour. This is a sign that the fluid needs to be changed or that there is a potential internal issue.

Unusual vibrations or shuddering

If you experience unusual vibrations or a shuddering sensation, particularly when shifting gears, it could indicate a misalignment or a problem with the transmission’s torque converter.

Reduced fuel efficiency

A malfunctioning transmission can lead to a decrease in fuel efficiency. This happens because the transmission may struggle to shift gears effectively, causing the engine to work harder and consume more fuel. If you notice that you’re burning through gas faster than usual, this could be why.

It’s important to note that these symptoms can vary depending on the make and model of your vehicle, and some may be more prevalent in an automatic transmission versus manual transmission. Regular transmission maintenance can help prevent many of these issues. If you notice any of these symptoms, consult a professional mechanic or transmission repair shop promptly to diagnose and address the issue before it worsens.

Signs of transmission problems unique to manual transmission vehicles

Manual transmission vehicles, like manual cars or all-terrain vehicles (ATVs), have some unique transmission problem signs that differ from those of automatic transmissions. If you own a manual vehicle, knowing these additional signs can help in early diagnosis. Here are key signs of transmission problems specific to manual vehicles:

Difficulty in shifting gears

If you find it hard to shift gears, or if the gear stick is unresponsive or sticks, this could be a sign of a problem with the transmission. This difficulty can be due to various issues, such as a failing clutch, worn-out gear synchros, or problems with the shift linkage.

Dragging clutch

A clutch that fails to disengage properly when you press the pedal (dragging) or a clutch that slips causing the engine to rev up without corresponding acceleration can indicate problems. These issues might stem from a worn clutch, a misadjusted clutch pedal, or a hydraulic system failure.

Abnormal clutch pedal behaviour

If the clutch pedal feels spongy, loose, sticks, or requires more effort to press, this could indicate an issue within the clutch assembly, such as a failing clutch master/slave cylinder, air in the hydraulic line, or a deteriorating clutch disc.

Unusual noises when the clutch is engaged or disengaged

Noises like squealing or chirping when engaging or disengaging the clutch can suggest problems with the clutch release bearing or pilot bearing. These bearings play crucial roles in clutch operation, and their failure can impact the transmission’s functionality.

Strange sounds that indicate transmission trouble

Hearing strange sounds like whining, clunking, grinding, or buzzing from your vehicle can be disconcerting, especially when they indicate potential transmission trouble. These sounds vary and can offer clues about the nature of the problem.

While we already mentioned above that strange sounds are a sign of transmission trouble, knowing the different types of sounds you may hear and what they mean can help you determine what the issue may be. Here’s a closer look at different types of strange sounds that may signal transmission issues:

Whining or humming

These noises are often continuous and can vary in intensity with the vehicle’s speed. Whining or humming might indicate a problem with the transmission fluid pump, which is crucial for maintaining adequate fluid pressure.

Low fluid levels due to leaks can also cause these sounds, as can bearings or other internal components that are wearing out. In automatic transmissions, a failing torque converter can produce a similar whine.

Clunking or chattering

Clunking sounds during shifting, especially in manual transmissions, can signify worn or damaged gear synchronizers. These components are responsible for smoothing out gear changes.

In automatic transmissions, a clunking noise might arise from problems with the hydraulic system, which controls gear shifts. Worn mounts or linkage can also produce a clunking sound, as they fail to hold the transmission steady during operation.


Grinding noises are particularly common in manual transmissions when the clutch is failing or not disengaging fully. This can cause the gears to grind against each other during shifts.

For automatic transmissions, a grinding sound might indicate problems within the planetary gear system, where damaged gears grind against each other or the gear housing.

Buzzing or clicking

These sounds can be more subtle but are no less significant. They often point to issues with transmission fluid pressure, which can be due to a variety of causes, such as a failing transmission pump, clogged filters, or leaks in the transmission lines. The sound occurs because the transmission is not receiving enough fluid to operate smoothly.


A rattling noise often suggests something is physically loose within the transmission. This could be a loose bolt or a broken part that’s moving around inside the transmission casing.

In some cases, it might also indicate a problem with the torque converter, especially if the noise is more noticeable at lower speeds.

Banging or knocking

These sounds are more severe and often indicate significant internal damage. Banging or knocking can occur when there’s excessive play in the transmission’s internal components, such as the gears or bearings. These sounds may be irregular but are often most noticeable during acceleration or when switching gears.

Squealing or screeching

While less common, a squealing or screeching noise, especially when starting the vehicle or changing gears, can indicate a problem with the transmission’s belt or chain.

In CVTs (Continuously Variable Transmissions), damaged or worn transmission bands can produce a screeching sound as they struggle to maintain their grip.

When diagnosing these sounds, it’s important to consider the nature of the noise, when it occurs (e.g., during shifting, at idle, during acceleration), and any accompanying symptoms like fluid leaks, burning smells, or warning lights. These details can help a mechanic pinpoint the specific issue.

Can auto insurance cover transmission problem expenses?

Typically, insurance policies like car insurance or motorcycle insurance cover damages to your vehicle caused by specific incidents outlined in the policy. However, when it comes to transmission problems, the coverage largely depends on the type of insurance you have and the cause of the transmission failure.

If you’ve noticed that your vehicle is experiencing transmission problems, you may wonder if your car insurance can help you cover the expensive repairs. Below, you’ll find a detailed explanation of how different types of auto insurance may help with your transmission problems.

Standard auto insurance

Most standard auto insurance policies, like third-party liability coverage, do not cover routine mechanical failures like transmission problems. These policies are primarily designed to cover damages resulting from sudden and accidental incidents.

Collision and comprehensive coverage

Collision insurance covers damage to your vehicle resulting from a collision, regardless of fault. If your transmission is damaged due to an accident, collision coverage may cover the repair costs.

Comprehensive insurance covers non-collision-related damages to your vehicle, such as those from theft, fire, or natural disasters. If your transmission is damaged due to a covered event under your comprehensive policy, it may pay for repairs.

Mechanical breakdown insurance (MBI)

MBI is a separate policy or an add-on that covers major mechanical components of the car, including the transmission. It functions similarly to an extended warranty from a car manufacturer but is provided by your insurance company. MBI typically covers the cost of repairing or replacing the transmission if it fails due to normal use or a defect. However, there are usually stipulations regarding the age and mileage of the vehicle for eligibility.

Warranty Coverage

While not insurance, it’s worth noting that a manufacturer’s or extended warranty might cover transmission repairs. When buying a new car, it comes with a factory warranty that usually includes the powertrain, covering the engine and transmission for a specified period.

Maintenance and wear and tear

Standard auto insurance policies do not cover routine maintenance and wear and tear. As such, it’s important to maintain your vehicle according to the manufacturer’s schedule to avoid such issues.

Regular maintenance, including fluid checks and clutch inspections, can help keep your manual transmission in good working order.

How to prevent transmission failure

Preventing transmission failure with regular maintenance is key to maintaining the longevity and reliability of your vehicle. The transmission is a complex and vital component, and taking proactive steps to care for it can save you from costly repairs down the line. Here are detailed strategies for preventing transmission failure:

Regularly check and change transmission fluid

The lifeblood of the transmission system is its fluid. Regular checks for the level and condition of the fluid are essential.

Over time, transmission fluid breaks down and loses its effectiveness. Old or dirty fluid can lead to increased friction and overheating, which are common causes of transmission damage.

Follow the manufacturer’s guidelines on when to change the transmission fluid, usually every 30,000 to 60,000 miles. However, this can vary based on driving habits and conditions.

Use the right type of transmission fluid

Automatic transmission fluid is typically thinner than manual transmission fluid, has detergents and other additives for hydraulic functionality, and may have friction modifiers.

Manual transmission fluid, on the other hand, is primarily for lubrication and is often thicker as it lacks the detergents and varied additives found in automatic transmission fluid.

Each transmission requires a specific type of fluid. Using the wrong type can lead to inadequate lubrication, overheating, and increased wear. Always consult your vehicle’s manual or a professional mechanic to ensure you use the appropriate fluid.

Inspect transmission seals and gaskets

Prevent fluid leaks by ensuring that seals and gaskets are in good condition. Leaks can lead to low fluid levels and increased wear on the transmission.

Service your transmission regularly

Regular transmission servicing includes more than just changing the fluid. It should also involve replacing the filter if applicable, checking for any leaks, and a thorough inspection for any signs of wear or damage. Regular servicing can help identify and address issues before they become major problems.

Avoid overheating

The transmission can overheat due to heavy use, such as frequent stop-and-go driving, hauling heavy loads, or towing. Overheating is one of the fastest ways to cause significant transmission damage. Installing an auxiliary transmission cooler can help, especially for vehicles under heavy strain.

Keep your cooling system in good shape

Since transmission fluid cooling happens in the radiator, a well-maintained cooling system is essential for preventing transmission overheating.

Warm up your vehicle in cold weather

In colder climates like Canada, allow your vehicle a few minutes to warm up during the winter before driving. This helps the transmission fluid reach its optimal operating temperature, ensuring smoother flow and better lubrication.

Avoid ‘rocking’ between gears

If stuck in snow or mud, resist the temptation to rock the vehicle back and forth between gears. This can create a lot of heat and stress on the transmission.

Avoid neutral at red lights

In automatic transmissions, constantly shifting into neutral at stops or while idling can cause additional wear over time. It’s generally best to leave the vehicle in drive.

Practice good driving habits

Avoid aggressive driving behaviours like rapid acceleration and hard braking. Smooth, steady acceleration and braking are better for your transmission’s longevity. For manual transmissions, ensure full clutch engagement during shifts to prevent grinding.

Use your parking brake

Utilize the parking brake when parked on a hill to reduce strain on the transmission. This prevents the entire weight of the vehicle from resting on the parking pawl in the transmission.

Address issues promptly

If you notice any signs of transmission problems, such as leaks, odd noises, or issues with shifting gears, get them checked by a professional immediately. Early intervention can prevent minor issues from escalating into major failures.

Protect both your vehicle and wallet with BrokerLink today

Understanding the symptoms of a bad transmission is crucial for any vehicle owner. By being vigilant about these signs, you can prevent extensive damage and potentially expensive repairs. As such, it’s important to remember that regular vehicle maintenance, including proper care of your transmission, plays a pivotal role in your car’s health.

If you’re someone who likes modifying your vehicle, be aware that certain modifications can impact the transmission’s performance. Additionally, always consider how modifications might affect your car insurance policy.

At BrokerLink, we’re committed to helping you navigate the complexities of car ownership, from ensuring you have the right car insurance in Toronto, Banff or Vancouver, to offering advice on vehicle maintenance and modifications. Remember, taking proactive steps today can save you from significant headaches and expenses down the road.

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