Toyota A750E / A750F

Toyota's longitudinal five-speed for the body-on-frame vehicles — the Hilux, Fortuner, Lexus GX and LX.

These are working vehicles, and everything about this transmission's failure pattern follows from that. They tow, they idle in heat, and they are driven in low range — all of which put work through the torque converter rather than the gearbox.

So the recurring complaint is a shudder or a slip that appears when the vehicle is hot and loaded, and disappears when it is not. That is the torque converter's lock-up clutch, and on a towing vehicle the fluid is what determines whether it wears out at 100,000 km or 300,000 — which makes an auxiliary cooler a preventative measure rather than an accessory.

The genuine internal wear is the direct clutch, presenting as a flare on the 3–4 change under load. Catching it early is the whole difference, because a slipping clutch fills the fluid with the material it is shedding and takes the rest of the transmission with it.

The A750F is the four-wheel-drive version, mechanically the same with a transfer case; a parts list for one is otherwise the parts list for the other.