Why a Joint Toyota-Mazda RWD Platform and Inline-6 Engine Makes Sense

A Mazda inline-six cylinder engine developed for a rear wheel-drive-based platform has been industry knowledge since news broke in May. But new reporting from Best Car in Japan confirm that Toyota/Lexus and Mazda will share that rear wheel-drive platform and inline-six engine.

Mazda’s inline-six engine development will include Skyativ-X (gasoline) and Skyativ-D (diesel) variants, mounted longitudinally. Additionally, a 48-volt mild-hybrid electrical system and all-wheel-drive variants will be offered. The question is what this has to do with Toyota.

First, this would not be a new relationship between the two Japanese carmakers. They are teaming up on a plant to build Corollas and a new crossover in Huntsville, AL. Whether that new model is exclusively a Mazda, or a shared platform with Toyota, remains to be seen. There are currently no decisive indications that it will be a shared platform, but it makes one wonder.

Toyota has figured out that low-volume models are not worth the investment in design, development, and manufacturing without teaming up with another manufacturer. As evidence, we’ve seen the joint Subaru development for the 86, the BMW partnership for the “Zupra” (can I trademark that?), and — let’s not forget — the Mazda 2 and Scion/Toyota iA. Mazda also teamed up with Fiat to turn the MX-5 in to the 124 Spyder and Abarth.

The effort to duplicate other manufacturer’s vehicles into Toyotas is minor compared to the entire product development budget. The economies of scale can be shown to enable the vehicles to be built profitably, but only when sharing development costs. Selling two versions under two brand names doesn’t hurt when the second brand is one as respected as Toyota.

Thus far, Toyota has leveraged other manufacturer’s platforms and powertrains, massaging them to fit in their showrooms. This allows them to focus on their strengths and leverage the more unique platforms from others. Development costs are highest when trying to do something new or different. Essentially, if it doesn’t fit into Toyota’s New Global Architecture, they’ll seek a partnership to fill that niche.

It works for both parties, too. Exchange of technology is often part of the deal, which can help the other manufacturers improve their strength in other market segments. They’re also selling more of the cars that they are manufacturing, helping to pay off those development costs and keep their plants profitable.

Toyota may be continuing the trend and, rather than designing their own next-generation RWD platform, they’ve opted to team up with another partner to distribute the development costs. The new inline-six engine might just be part of the deal. They didn’t change the engines in the iA, 86, or Z4/Supra, as that would negate the cost sharing benefits.

The new platform could either be a Mazda6 replacement, or supplemental premium sedan. According to Best Car, the Lexus IS is slated to be moved to a TNGA platform, with V6 power. While the shared platform could replace the Lexus IS for the 2022 Model Year, it seems counter-intuitive that the car would be developed and replaced only two years later. They speculate a new coupe that sits between the RC and LC, though that also seems like a narrow gap to shoot for.

What would make sense to me is if the IS platform was stretched for another couple years by a minor model change. Then, the new platform would underpin the next IS sedan and RC coupe. If they are to actually hit the 2022 MY deployment, then early prototypes should be running around as soon as next year.

[Images: Mazda]