The input shaft is the same spline as the W56/8 but longer. the output spline is bigger but is the same as the A340 series automatic gearboxs (autos in supras/soarers and also the 3rz hilux)
Overall they are bigger in diameter.
And the big one is price if the seller is selling a genuine r154, and not trying to rip people off.
Good luck.
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