Automatic transmission

Types of Automatic Transmissions

An automatic transmission is a gearbox that automatically changes the vehicle's speed as it moves, allowing the driver to operate the accelerator and brake pedals without using the clutch. The types of automatic transmission are:

• Hydraulic Automatic Transmission

  Hydraulic automatic transmissions, or ATs, utilize a fluid coupling, or torque converter, to transfer power from the engine to the transmission. The torque converter traps a specific amount of liquid between two impellers, which are similar to blades on a waterwheel. One set of blades is connected to the engine, and the other is connected to the transmission, which allows the vehicle to come to a complete stop without stalling the engine. The AT also uses planetary gear sets, hydraulic controls, and friction elements, such as clutches and brakes, to change gears automatically. Most cars today use this type of transmission because it is simple and efficient.

• Continuously Variable Transmission (CVT)

  A continuously variable transmission (CVT) is a type of automatic transmission that is designed to keep the engine running at the most efficient speed, regardless of the vehicle's speed. CVTs use two pulleys and a belt instead of fixed gears. One pulley changes in size to fit the driver's need for more or less power, while the other pulley expands or contracts to match. As a result, the engine can rev up smoothly and maintain the right power level without any noticeable gear changes. This transmission is commonly found in hybrid and electric vehicles.

• Dual-Clutch Transmission (DCT)

  A dual-clutch transmission (DCT) is designed to deliver high performance and efficiency. This type of transmission has two separate clutches—one for the odd-numbered gears and one for the even-numbered gears. This setup allows for super-fast gear changes without any interruptions in power delivery. DCTs are popular in sports cars and high-performance vehicles, making them ideal for drivers who want extra speed and control.

In conclusion, choosing the right transmission type depends on the driving experience, vehicle performance, and fuel efficiency needs. Each transmission type offers distinct features and advantages, catering to a wide range of preferences and requirements.

Specification and maintenance of automatic transmission

A well-built and maintained automatic transmission has a long service life, up to 100,000-200,000 miles or more. The specifications of the transmission vary depending on the type of vehicle and the manufacturer's design. Here are some common ones:

• Transmission fluid: Transmission fluid is the most important maintenance part of maintenance. Transmission fluid lubricates and protects the internal components of the gearbox. The fluid should be checked regularly to see that it is at the recommended level and in good condition. The fluid level should be checked using the dipstick. The fluid level may differ, depending on the vehicle and the transmission type. The fluid should be changed according to the manufacturer's recommendations, at least every 30,000-60,000 miles. The fluid change helps remove debris and contaminants that accumulate over time. The old fluid is drained out, and the new fluid is filled in through the fill hole.
• Transmission filter: The filter helps remove dirt and debris from the transmission fluid to help keep the fluid clean. The filter should be replaced every 30,000-60,000 miles, depending on the manufacturer's recommendations. To replace the filter, the transmission pan is removed, and the old filter is taken out. The new filter is installed, and the pan is put back.
• Transmission cooler: The cooler helps keep the transmission fluid at a stable temperature. The cooler should be checked to see that there are no leaks or blockages. The pipes and fittings should be inspected for cracks or damage. The cooler should be replaced if it is not functioning properly.
• Seals and gaskets: The automatic transmission has many seals and gaskets that prevent fluid leaks. The seals and gaskets should be checked for cracks, wear, or leaks. The signs of wear include dampness or moisture around the transmission parts. The seals and gaskets should be replaced if there are any signs of damage.

By following these tips, the transmission can be kept in good condition and its service life lengthened.

How to Choose an Automatic Transmission

When choosing automatic transmissions for business, consider the transmission type, compatibility with various driving conditions, gear ratio range, and reliability.

• Transmission type

  There are several types of automatic transmissions. Each has its advantages and limitations. For example, while dual-clutch transmissions have quick shift times, they may not perform well on steep inclines. Consider the driving conditions the vehicles will be used in and the type of transmission that will be more suitable.

• Compatibility with driving conditions

  Some automatic transmissions are designed for specific driving conditions, such as city driving, off-road, or highway driving. For example, vehicles with a manual transmission are better suited for off-road driving because drivers can better control the vehicle's power. If the vehicle is to be used for delivery in urban settings, transmissions that provide smooth gear changes at lower speeds are ideal.

• Gear ratio range

  The gear ratio range is important because it affects the vehicle's acceleration, fuel efficiency, and ability to handle various driving conditions. A wider gear ratio range allows the vehicle to adapt to different situations. For example, the transmission can provide more power when going uphill and better fuel efficiency on the highway. Consider the business's specific needs, such as cargo loading capacity, required speed, and terrain challenges when selecting the gear ratio.

• Reliability

  Automatic transmissions with a reputation for reliability are ideal. Research manufacturers and the estimated lifespan of their transmissions to avoid costly repairs and replacements. Consider the warranty and support from the supplier or manufacturer in case of defects or issues with the transmission.

How to DIY and Replace Automatic Transmission

Many people are afraid of DIY transmission fluid changes because they don't want to mess with their cars. Liquid maintenance is not as scary as it seems, and there are a few things to keep in mind to ensure everything goes smoothly. First, make sure the vehicle is on a level surface. This is important for getting an accurate reading of the transmission fluid level. Second, always use the type of transmission fluid recommended by the manufacturer. Using the wrong type can cause damage to the transmission over time.

Before starting, gather all the necessary tools and materials. This includes new transmission fluid, a funnel, a drain pan, and possibly a new transmission filter (depending on the vehicle's needs). Check the owner's manual for the recommended transmission fluid type and the interval for fluid changes. Setting up a work area where the vehicle has enough space to work underneath and around it is essential.

With the car parked on a level surface, engage the parking brake and start the engine. Allow it to run for a few minutes so the transmission fluid can warm up. Warming up the fluid makes it easier to drain and ensures an accurate level when refilling. While the engine runs, press the brake pedal and move the gear selector through the various gears (e.g., from P to R to N to D and back to P). This helps circulate the fluid and provides a complete change when draining.

Locate the transmission fluid dipstick (often labeled) and remove it. Wipe it clean with a lint-free cloth or paper towel, then reinsert it and remove it again to check the fluid level. This initial check provides a baseline for the fluid level before any work is done. Next, turn off the engine and prepare to drain the old fluid. Depending on the vehicle, there may be a drain plug on the transmission pan, or the fluid may need to be drained by removing the pan. Either way, use a drain pan to catch the old fluid and dispose of it properly.

After draining, remove and replace the transmission filter if the vehicle has one. This helps capture any contaminants and ensures a complete fluid change. Reinstall the drain pan or transmission pan, making sure to use new gaskets or seals if needed to prevent leaks. Now, it's time to add new transmission fluid. Through the dipstick tube, use a funnel to pour in the recommended amount of new fluid. Start with a smaller amount, then check the level and adjust as needed.

After adding the new fluid, start the engine and let it run for a few minutes. Then, cycle through the gears again, and recheck the fluid level with the dipstick. Add more fluid if necessary to reach the correct level. Remember, overfilling can cause transmission problems. Finally, take a test drive to ensure everything works properly. When finished, clean up any spills and properly dispose of the old fluid and any other materials used during the process.

Q&A

Q1. Are there any vehicles that cannot use automatic transmissions?

A1. Most modern vehicles can use automatic transmissions. However, some very small cars, sports cars, or heavy-duty trucks might use different types. These types might be better for their specific needs.

Q2. Can an automatic transmission be converted to a manual transmission, and vice versa?

A2. Yes, it is possible to convert between transmission types. However, it requires significant modifications and can be quite expensive. The conversion affects the vehicle's performance and requires thorough adjustments.

Q3. Can beginners learn to drive with an automatic transmission car?

A3. Yes, it's often easier for beginners to learn to drive with an automatic transmission car. They don't have to worry about changing gears or using a clutch, allowing them to focus on the road and traffic.

Q4. Do automatic transmission cars have better fuel efficiency?

A4. Automatic transmissions used to consume more fuel than manuals. However, technology has advanced, and today's automatic transmissions can be as fuel-efficient as manuals, if not better in some cases.