A fresh report out of Australia claims the upcoming Toyota Land Cruiser 300 will indeed feature six-cylinder turbodiesel power, though the engine will come from Mazda.

While there have been plenty of rumours about exactly what will power the impending follow-up to the Land Cruiser 200, this latest one is particularly interesting.

According to motoring.com.au’s “well-placed sources”, the Land Cruiser 300 will “almost certainly” employ a new 3,3-litre straight-six turbodiesel unit (rather than the previously rumoured V6) being developed by Mazda for its next-generation CX-5 and Mazda6.

Back in November, Mazda confirmed plans to start rolling out new six-cylinder engines by 2022. If the latest Land Cruiser 300 rumour turns out to be accurate, that’d suggest Toyota would debut the fresh straight-six unit before Mazda.

A leaked slide from May 2020 claimed Mazda’s upcoming 3,3-litre turbodiesel mill would generate 210 kW and 600 N.m. If the Land Cruiser 300 does end up employing this engine, it’s not yet clear if the outputs would be tweaked. In addition, an earlier report claimed the next-generation Hilux range would gain a full-fat GR derivative, complete with six-cylinder power. Based on this latest rumour, that suggests the GR Hilux could end up using Mazda's inline-six engine.

As a reminder, the two automakers have a wide-ranging partnership in place, with Toyota set to start building a new SUV (CX-7 revival, anyone?) for Mazda at its Alabama factory and the next-generation Mazda2 rumoured to be based on the Yaris. Under the broader tie-up, Mazda is expected to employ some of Toyota’s hybrid technology, while Toyota will gain Mazda’s latest combustion engines.

The new Land Cruiser 300 is expected to hit the market in Japan later in 2021, initially powered by the aforementioned diesel unit. The oil-burning powerplant is tipped to be joined by a twin-turbo 3,5-litre V6 petrol engine (depending on the market, of course), with an electrified version of the latter likely to follow at a later stage. The Land Cruiser 300 is widely expected to ditch both the 4,5-litre turbodiesel V8 offered in South Africa and the 4,6-litre petrol V8 sold in some other markets.