TBall, I appreciate your interest to help me, but...
Now, I am sure there is a confusion, as far as I know, "active traction", only works when the F.J. is 4L, that implies that the F.J. is in engaged in 4WD, and goes at a very slow speed.
There is no way, to drive the F.J. only with rear wheels.
My doubt remains unsolved.
Thanks any way.
Manolo