Aisin AB60F / AWR10L65

Aisin's heavy rear-drive automatics — the six-speed AB60F and the ten-speed AWR10L65 — in Land Cruisers, the Lexus LX, the Tundra and the Sequoia.

⚑ These are the gearboxes behind Toyota's V8s and big sixes, built for towing and for sustained load, and they are physically enormous. Access is the practical difficulty: a job that is routine on a transverse Aisin is a subframe-out proposition here.

Heat is what shapes their life, as it is on every gearbox that tows. A cooler, a temperature gauge and a shortened fluid interval are what owners who work these vehicles fit — and the stated lifetime fill is a statement about ordinary use, not about towing.

The AWR10L65 is a recent ten-speed and shares its architecture with Aisin's other modern units rather than with the AB60F it replaced, so their habits do not transfer.

Their reputation is very good, and reported failures cluster hard on vehicles that towed without a cooler.

AB60F is a six-speed and AWR10L65 a ten. They are a generation apart in the same heavy-duty Toyota line, so a procedure written for one is very often the wrong document for the other.