What is Car Transmission System? Definition, Parts, Types, Cost

What is Car Transmission System? Let’s say you just got a call from your transmission service and they say you need to have it repaired. The first question you would probably ask if you were to get this done is whether it would cost me anything. A rebuilt transmission may also take a long time to complete. The repair of this part may take some time due to the fact that it is crucial for the functionality of the car.

In order for your car to work properly, the transmission is one of the most important systems.  There are two types of automatic transmissions: manual transmissions and automatic transmissions.  It can be expensive to repair a transmission. These factors determine how much you will have to pay to get your vehicle back on the road.

Define Car Transmission System

The road wheels receive power from the internal combustion engine. Rotation of the crankshaft provides the engine’s output. This rotary motion transmits power to the wheels.

Automobiles move due to the friction between the road and the wheel surface. This function is performed by the transmission system. There are several components that make up the automobile transmission system. To transmit rotary motion from the crankshaft to the road wheels smoothly and efficiently, these components work together.

what transmission system definition parts types cost
What transmission system definition parts types cost

It is not desirable to change from rest to motion or vice versa suddenly. Automobile occupants may find it uncomfortable, or even dangerous. As a result, the crankshaft should rotate gradually and not suddenly. When the engine starts, the motion from the crankshaft should not be transmitted immediately.

Also Read: Types of Cars

Parts of Car Transmission System


The gear wheels are arranged in pairs. Through the clutch, they transmit the crankshaft’s motion at varying speeds. As a result, there is sufficient leverage between the engine and the road wheels. To deal with the different conditions encountered during the movement of the vehicle, the leverage is variable.

DSG Gearbox

As there is a clutch in the car, the DSG gearbox is in a sense a mix between a manual and automatic transmission. A fully automatic gearbox like this is not common. Dual clutches are used, which provide easy and quick gear changes without a clutch pedal.

In general, this gearbox is found in large German fleets such as Audi, and Volkswagen.  When it comes to maintenance, DSG gearboxes need more attention. Make sure you get service on the DSG gearbox, as it can only last a relatively short time compared to a manual gearbox. Gearbox gears may be affected by wear-related dust and sediment after 38,000 miles, so a service inspection is recommended every 38,000 miles.  

Sequential Gearbox

In sequential gearboxes, as the name implies, you have to pass each gear regardless of whether you are going up or down. Unlike a manual gearbox, you can switch between gears only after or before the current one as you shift gears on a pair of cogwheels. 

Unlike a manual transmission, which uses the H format, the gears in the automatic transmission are in line. Furthermore, sequential gearboxes allow faster gear shifting and faster acceleration, so they are used in many racing cars.

Also read: Types of bikes

Semi Automatic Gearbox

A semi-automatic gearbox maintains gear changes automatically with a computer instead of a clutch pedal. In practice, semi-automatic gearboxes work differently from car to car. When changing gears in some cars, you don’t have to do anything at all because the engine and electronics handle everything.

When you want to gear up or down, you need to tell the engine. Electronics shift gears for you when you push the gear lever. It is an actuator that actually makes the change.

The final choice is whether to use the gear stick for gear changes or go completely hands-free in other cars.


As the axis of the propeller shaft and live axle are at right angles to one another, the transmission system must turn the motion through 90 degrees. Through a wheel and pinion arrangement, the differential performs this function.

When the vehicle takes a turn, the differential also controls the difference in speed between inner and outer wheels.


This axle transfers motion from the crankshaft of the engine to the transmission. Dead axles or axles are axles that take up only the weight of the vehicle.

The motion is generally transferred to the rear axle, but it can also be transferred to both axles & the front axle. Four-wheel drive refers to the transfer of motion to both axles.

At the two ends of the axle, motion is transferred to the road wheels. Vehicles move on roads thanks to friction between their wheels and the road surface.

Propeller Shaft

As part of an automobile transmission system, it transmits motion between the gearbox and the differential. Because of the distance between them, a long, thin shaft is required to connect them.


The engine can stay disconnected from the road wheels by using this component.

It is not possible to transfer the rotary motion available at the crankshaft to the road wheels. When the driver desires, it allows the vehicle to transfer motion. Additionally, it allows the vehicle to be moved gradually by transferring motion gradually. Friction is the basis of its operation.

Also Read: What is Governer

Workflow of Car Transmission

The vehicle should not move as soon as the engine starts. It is only necessary to transmit the motion when you wish to do so.

An average car can cruise comfortably at 50 kilometers per hour on a properly maintained road, and with a wheel diameter of 30 cm, it will rotate at about 1060 revolutions per minute.

The inner and outer wheels will traverse circles of different radii if the automobile follows a circular path. As a result, the outer and inner wheels travel at different speeds. In an automobile, different distances are covered during the same period of time because it moves as a single unit.


Crankshaft rotation produces torque, which is transmitted to road wheels as a propulsive force or tractive effort, causing wheels to move.

A great tractive effort is required when starting from rest. There is almost no difference in torque produced by the engines. It is necessary to increase this torque in order to produce enough tractive effort.

The engine torque falls off at high engine speeds, so the tractive effort available would be less, reducing the road speed.


The engine and road wheels must be leveraged in order to accomplish this. Using the same leverage for climbing and moving on level terrain would result in an unduly low maximum speed.

At a moderate road, the engine speed would be very high since leverage implies a large reduction in speed between the engine and the wheels.

Carriage Unit

Carriage unit form does not greatly affect transmission nature.  The arrangement of transmission in a 4-wheel drive vehicle will be different from that of a rear-wheel drive vehicle.

The engine is usually mounted on the frame of the carriage unit at the front of the vehicle. Road wheels on the rear usually transmit motion to the front wheels. There is a considerable distance between them. For motion to be transmitted, this distance must be traversed. In addition, springs attach the rear axle to the frame.

In addition to the axle moving up and down, the springs flex due to the uneven surface of the road. Taking advantage of it requires engine positions, axle changes, and transmission systems to be able to handle it.

Also Read: What is Engine

Types of Car Transmission System

Manual Transmission

Transmissions control how much power is transmitted to the wheels at any given speed from an engine. As an example, let’s look at the gears on a bike. Shifting between them temporarily lifts and then reattaches the chain.

Similarly, a manual transmission operates in a similar manner. Shifting into a different gear is possible by pressing the clutch in, which disconnects the engine from the transmission. Upon releasing the clutch, the two are reengaged.  

Automatic Transmission

Automatic transmissions are essentially automatic gear shifters. To determine when to shift, the torque converter uses a torque converter, which moves to a higher gear as you speed up, and to a lower gear as you slow down.  

During acceleration, you may hear your engine get louder, & then drop as you accelerate. The gear shift indicates that your car is moving from a lower to a higher gear. The more gears an automatic transmission has, the more efficient it is. A vehicle with more gears will perform optimally at a wider range of speeds, resulting in greater fuel efficiency.

Automatic Manual Transmission

In the automatic manual transmission, a mechanical clutch is also used. Instead of being controlled by the driver, or by the clutch pedal, the clutch is controlled electronically, pneumatically, or hydraulically. It is also known as a Sequential Manual Gearbox or Direct Shift Gearbox. The gear selector, buttons, or paddles on the steering wheel can be used either for fully automatic forward gear shifts or manual shifts. 

Continuously Variable Transmission(CVT)

Continuously variable transmissions are also called shiftless transmissions and are abbreviated CVT. A continuous range of effective gear ratios can be achieved with this modification to an automatic transmission as opposed to a fixed number of gear ratios. Belts, pulleys, and sensors in the transmission system maintain a steady acceleration without changing gears on a regular basis. Compared to manual transmissions, belt-driven transmissions have an efficiency of approximately 90 percent. By keeping the engine at its best power, the CVT increases the engine’s efficiency and mileage.

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Symptoms of Broken Transmission

The only person who knows your car better than anyone is you. As the only person who drives your car most often, you are the one who knows the most about it. As a result, if things turn out differently, you know something is wrong. Your transmission may be failing if this happens. If your transmission isn’t working correctly, you may need to have it repaired. There are some symptoms of a failing transmission that you should always be aware of.

Gear Shifting

There may be a problem with your transmission if this happens. Your transmission system may have a leak of transmission oil. Overheating your transmission and damaging other system components can occur if this is left on too long.

It is possible for your transmission to overheat if the transmission fluid is not able to reach the other parts. When these parts become hot, the liquid cools them down and lubricates them. When this problem occurs, if you don’t fix it right away, you may need a transmission repair.

Car Jerking

There is a good chance that your transmission is having trouble if it shakes or jerks. Manual transmission vehicles are prone to gear grinding. It is common for automatic transmission failure to begin with some hesitation during gear shifting. There are some who might describe this as slipping. As a result, the vehicle may shake or tremble when shifting.

These symptoms can also be caused by other factors. Clunks and jerks between gears are common due to engine and transmission mounts. In order to determine the true cause of the problem, you should take your vehicle to a repair expert as soon as possible.

Burning Smell

If you smell something burning while driving along your normal route, you should stop and have your transmission inspected by a mechanic. It is possible that there is a leak in the transmission fluid or that the transmission oil is low.

In the absence of immediate action, this will result in a damaged transmission. Using the dipstick on the transmission, you can check the fluid level. You will have to spend a lot of money repairing your transmission if you let this burn for too long.

Also Read: Gear Box

Humming Noise

It is not a good sign if your car makes noise while you are driving. Noises generated by your car while you drive are not normal. Your transmission may be clicking, humming, or buzzing.

A damaged gear or a poor bearing could cause this. You may hear this buzz if your gear oil is running low. This sound will alert you to the fact that something is wrong, regardless of what the problem is. A transmission repair may be needed in the future if you don’t figure out what the problem is.

Fluid Leaking

Your vehicle may be leaking transmission fluid if you see red fluid under it. Gaskets, radiator pipes, and seals can cause this. The fluid leaks on the hot pipes and eventually damages the working parts of the transmission.

It is important to find the root cause of this leak as soon as possible. In the case of a transmission that has been sitting in its fluid for an extended period of time, you will most likely have to replace the entire transmission.

Slipping Transmission

You feel like you’re driving in a gear and then the transmission changes without warning when you notice transmission slippage. A whining noise may also be heard in this case. It is important that you fix your transmission as soon as possible if this happens to you while you are driving.

There are a number of reasons why this can happen, including low transmission fluid or inadequate maintenance. The entire transmission system may wear out as a result. As a result, your transmission will need to be repaired.  

Clogged Transmission Fluid Filter

You may not know that your transmission has a filter that screens out dirt, dust, and metallic flakes before they create havoc. Filters can become clogged once they screen out enough debris, rendering them ineffective. Moreover, it can also block the flow of fluid, causing the same problem as the first two.

Transmission fluid and filter should be changed every 30,000-60,000 miles to keep your transmission healthy. You will also be able to catch small problems before they become big ones by doing this.

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Noisy Neutral

Make sure you start your car in neutral and let it run. Neither bumps nor other noises are present. The engine of your vehicle should run quietly.  The most common issues can be fixed by changing the transmission fluid if you hear extra noises that weren’t there before. 

Ensure that you don’t overfill your transmission fluid if you do it yourself. This could cause even more damage to your vehicle. Look up the factory specifications to find out how much you need to add.  Your car needs to be checked out if the noises don’t go away. 

Transmission System Problem

Putting your vehicle in gear and having it not move is a frustrating experience. As soon as your car starts moving, you expect it to move. Your transmission may be malfunctioning if it doesn’t move. The transmission system can be affected by this problem. To prevent damage and to ensure that your transmission performs well, you must properly maintain it.

If the fluid level is not checked or debris is not removed occasionally, the transmission can be severely damaged. Your transmission will most likely need to be repaired in this case.

Engine Light Checking

You are alerted when there is a problem with your car by this. The source of the problem should be investigated. You don’t necessarily have a problem with your engine if the engine’s indicator light comes on. It is common for people to automatically assume that it is the engine.

If your transmission is having problems, the light will also come on. The transmission can be slipping, have a problem with the solenoid, or overheating due to a number of reasons. 

You should seek help right away once you have identified the problem. Your transmission may need to be repaired if the light appears.

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Repair Cost of Your Transmission System

Transmission repair is one of the most expensive jobs a mechanic can perform. Due to its importance to the functioning of the car, the transmission is expensive to repair. Depending on many factors, the cost of repairing a transmission ranges from 1,800 dollars to 3,400 dollars.

When it comes to repairing a transmission, you have a few options. It costs between 800 dollars and 1,500 dollars to purchase a used transmission. Rebuilt transmissions cost between 1,100 dollars and 2,800 dollars, and refurbished transmissions cost between 1,300 dollars and 3,400 dollars.

The transmission costs exactly what is listed here. Furthermore, labor costs must be paid. The cost of removing and repairing a transmission ranges from 500 to 1,200 dollars. Mechanics can complete this job in four to ten hours.

Replacing a transmission is more expensive than buying a rebuilt system. All depends on how much damage has been done. Transmissions from high-end vehicles or highly regarded mechanics are usually more expensive.

You will spend the least amount of money on basic repairs. The cost will range from 300 to 1,400 dollars. Repairing your transmission will cost you based on many factors. Your car type, the type of transmission you purchased, and the mechanic you choose will all determine how much it will cost.

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Cost Effecting Methods for Transmission Repair

The best course of action is prevention rather than an amendment. To keep the cost of automatic transmission maintenance low, it is vital to remember some key points. In order to avoid costly transmission repairs, check the warning signs before a complete breakdown occur.

Transmission repair costs can range from $150 to $2,500, depending on the problem. The severity and cost of the problem vary greatly, as you can see. 

Transmission repair costs can range from $150 to $2,500, depending on the problem. The severity and cost of the problem vary greatly, as you can see. 

By ignoring the problem, other things will go wrong and more components will malfunction. 

Shift Solenoid Replacement

It regulates how much fluid flows through the transmission with regard to the shift solenoid. Including parts and labor, replacing a solenoid can cost anywhere from $150 to $400. Solenoid costs can add up quickly in transmissions with two or more solenoids.

Check the Computer System

The problem may be with the computer system if it cannot read the RPM correctly. The cost of repairing a transmission can be reduced in a few ways. The local repair shop can install a remanufactured transmission that you purchased yourself. 

Buying the transmission yourself and having a mechanic install it is cheaper. Expenses associated with transmission repairs can be difficult to plan for financially. You can expect to spend between $1,800 and $3,400 on transmission repair.

Also Read: Power Steering Fluid

Key Factors of Transmission Cost

Transmission repair costs are determined by a variety of factors. The type and extent of the repair are the most important factors. A complete transmission repair can cost thousands of dollars.

Depending on Transmission

Automatic transmissions typically cost more than manual transmissions. Your transmission may need to be checked if you start experiencing problems. Your car will be unable to run if you ignore it.

Transmission Rebuild

There is a lot of labor involved in rebuilding a transmission. A transmission needs to be repaired in several steps. In order to diagnose transmission problems, mechanics disassemble the transmission. Any malfunctioning parts must then be replaced. Before repairing a transmission, a mechanic must check these three aspects.

Fluid should be changed first. Transmissions will not function properly if the transmission fluid is dirty or low. Error codes need to be checked next. Automatic shifting is controlled by a computer system in the vehicle.

The sensors need to be replaced by a mechanic. Testing and inspecting the car is the last step before starting any transmission repair. The transmission can be repaired once all of these steps have been completed.

Transmission Fluid Leak

It costs as much as $200 to replace a worn seal that causes transmission leaks. This amount will increase significantly if the leak is caused by the front seal.

Seal swell agents are found in most transmission fluids, which prevent them from drying out and shrinking. Transmission seals can also be maintained with specific additives.

Fluid Flush

The service involves removing all of the old transmission fluid and replacing it with new fluid. The cost of a vehicle inspection can range from $80 to $250, depending on where you take it. To cut these costs in half, you can also do it at home.

Pricing of Repair Shop

The cost of repairing a transmission varies from repair shop to repair shop. Normally, it depends on the shop’s location and reputation. Your transmission may be failing if it sounds like it is humming, buzzing, or clunking. Humming, buzzing, and whining noises may be heard from a bad automatic transmission, while harsher & clunking noises can be heard from a bad manual transmission.

Type of the Car

It is common for US models to be less expensive cars than imported models. There will be a difference in the price of your transmission if this is the case. 

You may have difficulty finding the correct parts if you have an older vehicle. As a result, finding these rare parts and repairing the transmission will be more expensive.

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There will be a higher labor cost if you live in an area where the cost of living is higher or the demand for services is higher. Your transmission repair will be more expensive as a result.

Damage limit to your Transmission

Having a well-maintained transmission is crucial, as well as if it has sustained a lot of wear and tear. How much the repair will cost depends on what your car has been through.

Transmission Replacement

The only thing worse than finding out your engine is dead has to replace your transmission. It costs between $4,000 and $8,000 to replace your transmission with a new one. You can lower these costs by replacing the rebuilt transmission that gives 2500 to 4000 dollars.

Requirements of Transmission System

  • The engine can stay disconnected from the road wheels if this option is enabled. Ideally, these should only be connected when needed.
  • When the engine is running, enable the wheels to be connected smoothly and gradually without jerks.
  • Allow the engine to leverage the road wheels. For different conditions, such as starting from rest, moving at uniform speed, or climbing a hill, the leverage should be variable.
  • Reduce the engine speed by enabling this option.
  • 90 degrees should be turned on the drive.
  • As the vehicle moves on a curved path, the outer and inner road wheels should run at different speeds.
  • The engine should be able to provide the relative motion between the road wheels and the engine when the road surface is uneven.

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Wrapping it Up

Keeping car payments out of your budget by rebuilding your transmission can save you a lot of money over the short-term. It is worth the initial cost for many people to rebuild their transmissions. You may have to spend more than twenty-five hundred dollars on rebuilding a transmission.

As a result, the driver does not have to change gears manually any more as this happens automatically. In the event that the car is moving forward, this process is very efficient. It is a very complex part of your car that works constantly in order to keep it working properly at all times. Due to the fact that they are used so often, they can wear out over a period of time.  

FAQs on Transmission System

Is it Money saving to repair transmission system?

You can save a lot of money on your car payments by rebuilding a transmission in the short-term. The initial cost of rebuilding a transmission is worth it for many people. It can cost up to 25 hundred dollars to rebuild a transmission in some cases.

Can you drive with damage Transmission?

You should only visit your local mechanic if you think your transmission is faulty. Your vehicle will literally be unable to drive if you have a bad transmission.

How much mile can a transmission last?

Transmissions can last over 200,000 miles for some but just over 10,000 miles for others.  A transmission’s lifespan is most significantly influenced by regular vehicle maintenance & good maintenance can extend its lifespan even further.


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