What are the main components of an automatic transmission?

3 Answers
SanMaria
07/24/25 11:38pm
The main components of an automatic transmission include: torque converter, planetary gear transmission mechanism, hydraulic control system, and oil filtration device. An automatic transmission, also known as an automatic gearbox, is generally a type of automotive transmission that can automatically change gear ratios while the vehicle is in motion, allowing the driver to avoid manual gear shifting. It is also used in large equipment such as railway locomotives. The automatic transmission is a device that can automatically shift gears based on the vehicle's speed and engine RPM, as opposed to a manual transmission. Currently, there are four common types of automotive automatic transmissions: hydraulic automatic transmission (AT), continuously variable transmission (CVT), automated manual transmission (AMT), and dual-clutch transmission (DCT).
Was this review help?
19
0
Share
EthanMarie
08/10/25 10:37am
The core components of an automatic transmission include several key parts. The torque converter is the most critical, as it uses hydraulic fluid to transfer power, replacing the clutch found in manual transmissions. The planetary gear set functions like a precision Rubik's cube, achieving multiple gears by combining different gear rings. The hydraulic system controls oil pressure, featuring an oil pump and various valves that use oil to actuate pistons for gear shifts. The electronic control unit acts as the brain of the transmission, determining when to shift up or down based on vehicle speed and throttle input. The housing encases all these components and includes a cooling system to prevent overheating. These parts work together seamlessly, allowing automatic gear shifts when you press the accelerator. However, with more components comes higher repair costs, so it's important to regularly change the transmission fluid to maintain performance.
Was this review help?
5
1
Share
Expand All
SanLondyn
09/26/25 7:13am
Ordinary car owners can actually give a rough explanation. It mainly involves the torque converter, which transmits power through rotating fluid; several sets of planetary gears handle different gear ratios; the valve body in the hydraulic system is like a water pipe network, where the oil pump pressurizes to facilitate gear shifting; the electronic control module monitors data in real-time to make decisions; there's also the transmission casing and radiator. Last time at the 4S shop, I heard the technician say that most automatic transmissions now use this structure, with Toyota and Volkswagen having slightly different logic. For daily use, avoid frequently flooring the accelerator for sudden acceleration, as it can easily burn out the solenoid valve, and repairs for that can cost five figures.
Was this review help?
18
3
Share
Expand All
More Forum Discussions

How to Test for a Faulty Car Alternator That's Not Generating Electricity?

Steps to test for a car alternator not generating electricity: 1. Set the multimeter knob to DC voltage 30V; 2. Connect the red probe to the alternator's "armature" terminal and the black probe to the casing; 3. Run the engine at medium speed or higher. The standard voltage for a 12V electrical system should be around 14V, while for a 24V system, it should be around 28V; 4. If the measured voltage matches the battery voltage, it indicates the alternator is not generating electricity. Reasons why a car alternator may not generate electricity: 1. Diode breakdown, failing to rectify; 2. Brushes stuck in the brush holder, preventing the alternator from being excited and thus not generating electricity; 3. No power to the rotor's field coil; 4. Phase-to-phase short circuit or grounding in the stator coil; 5. Loose rotor claw poles.
15
3
Share

What to do with ETC after a car is scrapped?

After a car is scrapped, the solution for ETC is: the car owner should bring their ID card, vehicle license, ETC card, and OBU device to the ETC customer service center to handle the removal procedure. Then, with the removal certificate issued by the ETC customer service center, they can go to the contracted bank to cancel the service. ETC, also known as Electronic Toll Collection, is a system that allows vehicles to pass through toll stations without stopping. It uses onboard equipment to identify the vehicle, record information, and automatically deduct the corresponding fee from a pre-bound IC card or bank account. It is an electronic toll collection system used for roads, bridges, and tunnels. With ETC, passing vehicles can be automatically identified and charged without stopping at the toll gate.
16
4
Share

What is the reason for the electronic steering lock failure in the Baojun 560 one-key start system?

Baojun 560 one-key start electronic steering lock failure may be caused by low voltage, the steering column lock not being unlocked, the control key signal not being recognized by the system, the steering column lock failing to unlock, or a steering column malfunction. Precautions for automotive electronic steering: The level of the power steering fluid should not fall below the lower limit marked on the dipstick. If a shortage is detected, the cause should be identified and the fluid should be replenished promptly. If the fluid level is too low, air can easily enter the pipeline. If bubbles appear on the surface of the power steering fluid after replenishment when turning the steering wheel, it indicates the presence of air in the pipeline. If the bubbles do not disappear when turning the steering wheel left or right and the steering remains heavy, the air in the pipeline should be purged. Consequences of electronic steering lock failure: Electronic steering lock failure in the Baojun 560 can cause the car to veer off course during driving, meaning the car will automatically steer to one side even when the steering wheel is kept straight. This may be caused by inaccurate front and rear wheel alignment or inconsistent alignment parameters, or by the left and right steering tie rods being bent, deformed, or having excessive clearance at the hinge.
16
3
Share

What is the appropriate tire pressure for a Mercedes-Benz C-Class?

The normal tire pressure range for a Mercedes-Benz C-Class is between 2.4-2.5 bar. Due to seasonal factors, the tire pressure can be increased by 0.2 bar in winter and decreased by 0.1 bar in summer. This data is based on the international GBT2978-2008 standard requirements. The Mercedes-Benz C-Class is equipped with an active tire pressure monitoring function. The dashboard displays a car model corresponding to the vehicle's orientation, with four wheels showing the tire pressure information for each position, allowing clear identification of any abnormal tire pressure. Generally, a tire pressure exceeding 2.8 bar is considered too high, while a pressure below 2.0 bar is too low. Hazards of overinflation: Reduced tire friction and adhesion, affecting braking performance; steering wheel vibration and deviation, reducing driving comfort; accelerated wear of the central tread pattern, shortening tire lifespan; increased vehicle vibration, indirectly affecting the lifespan of other components; excessive tension on tire cords, reducing elasticity and increasing the load on the vehicle during driving. Hazards of underinflation: Increased friction coefficient with the road surface, leading to higher fuel consumption; heavy steering wheel and deviation, compromising driving safety; excessive movement of tire parts, causing abnormal heat generation; reduced functionality of cords and rubber, leading to delamination or cord breakage and excessive friction with the rim, damaging the tire bead area and causing abnormal wear; multiplied friction between the tire and the ground, sharply increasing tire temperature, softening the tire, and drastically reducing strength. High-speed driving may result in a tire blowout. If the tire pressure monitoring indicator light (a yellow symbol with an irregular circle, no stamp on top, four small spikes below, and an exclamation mark inside) illuminates, it generally indicates one of the following three reasons: Abnormal tire pressure: Typically, an alarm is triggered when the pressure is below 1.8 bar or above 3.0 bar. In this case, a tire inspection and pressure adjustment are required. Tire pressure monitoring not reset: After inflating the tires, if the tire pressure is not reset in time, the system will still record the previous data, causing the indicator light to illuminate. Simply reset the tire pressure to resolve this issue. Damaged tire pressure sensor: The tire pressure sensor, installed inside the tire and connected to the inflation valve, monitors tire pressure. If the sensor is damaged during driving (e.g., by impact), the tire pressure warning light will illuminate. For sensor damage, the only solution is to replace it with a new component.
15
3
Share

What are the automotive environmental protection standard levels?

Automotive environmental protection standard levels are divided into three categories: Euro I, Euro II, and Euro III. The European regulatory standards for vehicle emissions had already implemented several phases before 1992. Europe began implementing Euro I in 1992, Euro II in 1996, and Euro III in 2000. China's national standards for vehicle emissions differ from European standards. The national standards are formulated based on China's specific conditions, while European standards are commonly adopted by member states of the European Community. For vehicles that meet environmental protection standards, the government issues graded emission standard labels in two main colors: yellow and green. These labels are issued after reviewing the vehicle model and emission standards, with the purpose of facilitating energy-saving and emission-reduction inspections as well as regular environmental protection checks for vehicles.
8
4
Share

What Gear Should You Engage When Parking a Manual Transmission Car on a Downhill Slope?

When parking a manual transmission car on a downhill slope, engage the reverse gear to prevent the vehicle from sliding forward. To start the car, first press the clutch pedal, shift to neutral, and after the engine starts, shift to the starting gear. The reverse gear, fully known as the reverse driving gear, is one of the three standard gears in a car. It is marked as 'R' on the gear console and is designed to allow the vehicle to move backward, serving as a special driving gear. The function of the reverse gear is quite straightforward: it enables the vehicle to move in the opposite direction, facilitating reversing. This function is indispensable for any automobile. In manual transmission models, the reverse gear also serves as a hill brake. Parking on a downhill slope can be achieved by engaging the reverse gear to mechanically lock the drive shaft.
12
0
Share
Cookie
Cookie Settings
© 2025 Servanan International Pte. Ltd.