Who makes transmissions for Toyota?
Most of Toyota’s automatic transmissions are built by Aisin Seiki Co., Ltd. (Aisin), which serves as the company’s primary external supplier. Toyota also develops some transmissions in‑house and has worked with other partners for niche models and regional needs.
In practice, Toyota relies on a mix of external partners and internal development. Aisin supplies the vast majority of conventional automatics and many of the hybrid transaxles used across Toyota’s lineup, while Toyota’s engineers contribute to design, calibration, and integration for specific technologies and markets. Over the years, other manufacturers have provided transmissions for select models or regions as part of evolving powertrain strategies.
Key players in Toyota's transmission supply chain
The following are the primary entities involved in building or supplying Toyota’s transmissions, with Aisin the dominant external contractor.
- Aisin Seiki Co., Ltd. (Aisin) — The principal supplier of automatic transmissions for most Toyota models worldwide, including many conventional automatics and hybrid transaxles developed with Toyota.
- Toyota in-house development and production — Toyota’s own teams contribute to the development and assembly of specific transmissions, particularly some hybrid systems and market-specific variants.
- Historic/other external partners — Over the years Toyota has worked with other firms for certain models or markets, such as the Magna Powertrain group (which includes the former Getrag business) for some gearboxes and CVTs; these arrangements have varied by generation and region.
Conclusion: Aisin remains the dominant external supplier for Toyota transmissions, while in-house development and selective partnerships fill gaps for hybrids and regional needs.
Hybrid transmissions and e-CVTs
Hybrid systems require specialized transaxles. The bulk of Toyota's electronic continuously variable transmissions (e-CVTs) are built from designs developed with Aisin and integrated with Toyota control software, with production and assembly taking place across supplier and Toyota facilities depending on the model line.
- Aisin's e-CVT family — Widely used in Toyota hybrids such as Prius, Camry Hybrid, RAV4 Hybrid, and others, combining electric motor, generator, and gearsets in a compact transaxle unit.
- In-house integration — Toyota engineers work on control systems, calibration, and system integration to optimize efficiency and performance.
Conclusion: For hybrid models, Aisin is typically the primary external source for the transaxle, complemented by Toyota’s in-house software and system integration work.
Summary
In short, Toyota’s transmissions are mainly manufactured by Aisin Seiki, a long‑standing supplier, with additional transmissions produced or assembled through Toyota’s own teams and selective partnerships for specific models, markets, and hybrid technologies. This multi‑source approach helps Toyota maintain a broad and flexible powertrain lineup while continuing to pursue efficiency and performance gains.
