Who makes Toyota automatic transmissions?
The vast majority of Toyota’s torque‑converter automatic transmissions are built by AISIN Seiki Co., Ltd. (AISIN), primarily through its Aisin AW division. Toyota also uses transmissions from other suppliers for select models and markets, but AISIN is by far the dominant source.
This article explains who makes Toyota automatic transmissions, how the supplier network has evolved, and what it means for maintenance and model variability across Toyota’s lineup, including electrified vehicles.
Primary suppliers for Toyota automatic transmissions
Below are the main sources of Toyota’s conventional torque‑converter automatics. This list highlights the primary supplier and the role of other partners in the broader supply ecosystem.
- — The dominant supplier of Toyota automatic transmissions, including the widely used 6‑speed, 8‑speed, and other torque‑converter units across a broad range of Toyota cars, SUVs, and trucks.
- — Supplies a minority of Toyota models with select automatic transmissions in certain markets, representing an alternative source beyond AISIN for specific applications.
In practice, AISIN (via its Aisin AW division) remains the core producer of Toyota’s conventional automatics, while ZF serves as a regional or model‑specific secondary supplier in some cases.
In‑house development and collaboration
Toyota has also pursued in‑house development and collaboration to advance its automatic transmission technology. A notable example is the Direct Shift 8‑speed automatic, which Toyota developed in partnership with AISIN. This transmission has been adopted across a wide range of Toyota and Lexus models, reflecting the brand’s strategy to combine in‑house engineering with AISIN manufacturing capability.
Hybrid and electrified transaxles
Hybrid and electrified Toyota models use a dedicated transaxle that integrates the gasoline engine, electric motor(s), and planetary gear sets. These hybrid/e‑CVT units are designed specifically for Toyota’s Hybrid Synergy Drive and involve collaboration with AISIN/Aisin AW and Toyota’s own engineering teams to optimize efficiency, performance, and reliability.
- — A specialized transmission architecture used in most Toyota hybrids (and some plug‑in variants) that combines electric motors with a planetary gear train. These units are developed with input from AISIN and Toyota’s engineering programs to ensure seamless hybrid operation and driveability.
Hybrid and electrified transmissions represent a distinct category from conventional torque‑converter automatics, but they remain a central part of Toyota’s broader transmission strategy, especially as the lineup shifts toward greater electrification.
Summary
For conventional automatic transmissions, AISIN Seiki (including Aisin AW) is the primary manufacturer supplying Toyota, with ZF providing select units for certain markets or models. Toyota also develops and deploys its own collaboration projects, such as the Direct Shift 8AT, to enhance performance and efficiency. In electrified models, Toyota uses a purpose‑built hybrid transaxle developed in collaboration with AISIN and Toyota engineers. Together, these arrangements form the backbone of Toyota’s automatic transmission supply chain across the global lineup.
Which automatic transmission does Toyota use?
Toyota has developed two new automatic transmissions―the 8-speed Direct Shift-8AT and the 10-speed Direct shift-10AT. For both, various measures were taken to minimize energy loss and heighten transmission efficiency.
Does Aisin make Toyota transmissions?
Aisin is a member of the Toyota Group of companies. Therefore, the transmissions of both manufacturers are often based on identical gearset concepts.
Are Toyotas known for transmission problems?
While Toyota vehicles are generally known for reliability, they can have transmission problems like other cars, especially with high mileage. Some reported issues include transmission fluid leaks, slipping gears, and rough or delayed shifting. Recent recalls have also addressed specific transmission issues in certain models, such as vehicles in neutral not properly disengaging from the drivetrain, and reports of transmission failures in some newer models like the Tacoma.
Common symptoms of Toyota transmission problems
- Leaking fluid: Look for red or reddish-brown fluid puddles under your car.
- Strange noises: Listen for clunking, whining, or grinding sounds, particularly when shifting.
- Rough or delayed shifting: Experience jerky shifts or a noticeable lag when changing gears.
- Gear slippage: The car may unexpectedly shift out of gear or the engine RPMs may increase without corresponding acceleration.
- Burning smell: A burning odor can indicate overheating transmission fluid.
- Check Engine light: The check engine light can be triggered by various transmission-related issues.
Recent specific issues
- Vehicle creep: A recall was issued for certain 2022-2024 Toyota Tundras, 2023-2024 Sequoia SUVs, and Lexus LX 600s because the transmission may not fully disengage in neutral, causing the vehicle to creep forward.
- 2024 Tacoma transmission failures: Some owners have reported serious transmission failures in new 2024 Tacoma models, including a case where a transmission failed after only 342 miles. Dealerships have replaced some of these transmissions under warranty.
What you can do
- Regularly check your transmission fluid level and color.
- If you notice any of the symptoms above, have a qualified technician inspect your transmission promptly.
- Stay up-to-date on recalls and have any necessary service performed.
Where are Toyota transmissions made?
Toyota Motor Manufacturing West Virginia
Toyota Motor Manufacturing West Virginia, Inc. is Toyota's only combined engine and transmission plant in North America.
