“Automatic” describes how the car handles clutch and gear changes—not one single transmission design. The three common types are the torque-converter automatic, the continuously variable transmission (CVT), and the dual-clutch transmission (DCT). They differ in how they transfer engine power and change ratios, which can affect how a car feels at low speeds and during acceleration. The best choice depends on the specific vehicle, not the transmission label alone.
How an automatic transmission works
An automatic transmission changes the relationship between engine speed and wheel speed without requiring the driver to operate a clutch pedal and select each gear. The three designs below automate that task using different mechanisms. Their behavior and efficiency depend on the transmission’s engineering and the vehicle it is installed in.
1. Torque-converter automatic
How it works
A conventional torque-converter automatic uses a fluid coupling called a torque converter between the engine and transmission. The converter transfers engine power to stepped gearsets, typically planetary gears. Ford describes this arrangement as a hydraulically operated system based on a torque converter and planetary gearing (Ford Australia).
What it can feel like
The torque converter can make pulling away and moving slowly smooth and easy to control. Mazda, for example, says its SKYACTIV-Drive design uses the converter below 5 mph. That speed is specific to Mazda’s system; it is not a universal operating threshold for torque-converter automatics (Mazda SKYACTIV Technology).
The Tool Desk
Outbyte PC Repair FREEClear out junk files and repair common Windows errorsFree Scan →Outbyte Driver Updater FREEScan for outdated or missing drivers - takes under a minuteDriver Scan →#1 Best Overall
- For use in 95% of vehicles including most CVTs in operation with US registered light duty applications
- High performance conditioning agents prolong seal elasticity to prevent leaks
- Improved durability & transmission life with anti-wear technology to avoid costly repairs
- Enhanced high & low temp performance supports transmission fluid in all weather situations
- Full synthetic formula with advanced additives protects against transmission breakdown better than conventional fluids
2. Continuously variable transmission (CVT)
How it works
A CVT varies the ratio between the engine and wheels continuously across a range, rather than selecting from a fixed set of stepped gears. CVT describes a ratio-changing design, not a single brand or universal hardware layout.
What it can feel like
Because the ratio can change without distinct gear steps, acceleration may feel smooth. Engine sound may also rise or settle in a way that does not track road speed like the stepped shifts in other transmissions.
Rank #2
- For use in 95% of vehicles including most CVTs in operation with US registered light duty applications
- High performance conditioning agents prolong seal elasticity to prevent leaks
- Improved durability & transmission life with anti-wear technology to avoid costly repairs
- Enhanced high & low temp performance supports transmission fluid in all weather situations
- Full synthetic formula with advanced additives protects against transmission breakdown better than conventional fluids
What efficiency claims mean
NHTSA’s technical support document explains that a CVT can, within its ratio range, keep the engine closer to an efficient operating point for the power required. This is a design advantage, not a guarantee that every CVT-equipped car will use less fuel in real-world driving than every car with another transmission type (NHTSA technical support document).
3. Dual-clutch transmission (DCT)
How it works
A DCT automates the clutch and gear-selection tasks while retaining a manual-style gear structure. Two clutches manage separate gear sets. Honda describes it as automating clutch and shift operations while keeping the structure of a manual transmission (Honda Global).
Quick wins for a faster PC:
Repair Windows errors before they cause bigger problemsFix Now →Scan for outdated or missing drivers - takes under a minuteDriver Scan →Rank #3
- Enhanced friction durability for smooth transmission performance
- Superior high temperature protection to effectively resist oxidation
- Unsurpassed protection against copper corrosion
- Broad scope of vehicle applications improves workshop efficiency and inventory management
- ATF Applications: Dexron VI (Dexron III, Dexron) Mercon LV (Mercon SP, Mercon V, Mercon) JASO 1A (03), JASO 1A LV (13) Toyota T IV, Toyota T III, Toyota WS Honda/Acura DW 1/Z 1 Nissan Matic D, Matic J, Matic S Hyundai/Kia SP IV, SP III Mazda ATF M-V, M-III, FZ Mitsubishi SP IV, SP III, IIM, II, PA, J3 VW/Audi (6, 8 and 9 speed automatics) - BMW/Mini (6, 8 and 9 speed automatics) Jaguar/Land Rover (6, 8 and 9 speed automatics) Porsche (6, 8 and 9 speed automatics) Volvo (6, 8 and 9 speed automatics) Volvo Transmission Oil 97342, AT102 Mercedes-Benz (7 and 9 speed automatics)
What it can feel like
A DCT generally gives the driver stepped gear changes, and shifts may be more perceptible than in some other automatic designs. Hyundai notes that shifts in its DCT may sometimes be felt or heard. Its 2025 owner manual describes one wet-clutch DCT with eight forward speeds and one reverse speed; those specifications apply to that vehicle, not to DCTs as a category. Hyundai summarizes the concept this way: “The dual clutch transmission can be thought of as an automatically shifting manual transmission” (Hyundai 2025 owner manual).
How the three types compare
| Transmission type | How it changes ratios | Commonly relevant driving feel | What to check for a specific car |
|---|---|---|---|
| Torque-converter automatic | A torque converter couples the engine to stepped gearsets, typically planetary gears. | Can provide smooth launches and controlled creeping at low speeds; behavior depends on the design. | The exact transmission design and its owner-manual service schedule. |
| CVT | Varies the ratio continuously within a range instead of selecting fixed steps. | Can feel smooth; engine sound may not rise and fall in step-like shifts. | The exact CVT design and its specified fluid and service requirements. |
| DCT | Uses two clutches to manage gear sets while automating clutch operation and shifts. | Provides stepped shifts; some designs make shifts noticeable, including at low speeds. | Whether the clutch design is wet or dry, plus the vehicle-specific service schedule. |
Which type should you choose?
Use the transmission type as a starting point, then assess the particular car. A torque-converter automatic may suit drivers who prioritize smooth low-speed movement; a CVT may suit those who prefer seamless ratio changes; a DCT may appeal to drivers who like stepped shifts. These are tendencies, not guarantees.
Rank #4
- Exceeds demands of automatic transmissions of most Chrysler, Dodge, Ram & other Stellantis vehicles
- High-efficiency conditioners protect and prolong the elasticity of seals, preventing leaks
- Advanced technology reduces wear, foaming, and oxidation while protecting transmission performance
- Superior high & low temp performance supports transmission fluid in all weather & driving situations
- Full synthetic formula with advanced additives protects against transmission breakdown better than conventional fluids
- Drive the exact model you are considering. Pay attention to take-off, creeping, stop-and-go traffic, and acceleration.
- Compare the vehicle’s own fuel-economy information. Transmission type alone does not establish which car will use less fuel.
- Check the owner’s manual for maintenance requirements. Fluid specifications and service schedules depend on the vehicle and transmission; do not assume one transmission type has a universal interval.
Where automated manuals fit
An automated manual transmission (AMT) is a related but separate category: it automates clutch and gear-shift tasks in a manual gearbox. AMT terminology and usage vary by market, and it is not one of the three types explained above.
Quick Recap
Best Value
- Backward compatible with previous Dexron automatic transmission fluids and can be used as a much-improved replacement for older vehicles/transmissions originally using previous Dexron fluids
- Improved performance over previous Dexron fluids in: friction durability, viscosity stability, aeration and foam control, and oxidation resistance
- Potential to enable improved fuel economy and longer transmission life
- Provides for extended drain intervals. Provides consistent shift performance, even in extreme conditions.
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
