I need some advise please. I have a 1990 FJ70. The one in my avatar. I would like to install electric activated diff locks as in the new 70 series dual cab. In other words I would like to install these with the pem switches in the cab. Would this be possible. The FJ70 has the same diffs than the 75 as far as I know.
Sure it can. I'm doing it on my BJ74. I've already got the front one in (I swapped in a complete axle assembly in the front). If you've got a 9.5" diff, you can just swap in the elock diff if you can find the necessary long-spline, long-side inner shaft for the front. That shaft is not available in the US or in Japan. Perhaps can be found elsewhere though? If you've got the 8" high-pinion front diff, it's a lot more work to drop the elock diff into the non-elock housing. Easier to just swap the whole assembly (which is what I did. )
For the rear, it must be a full float axle assembly--which mine is--so all you need is the locking diff, a long-spline short-side axle shaft (available from Japan as of a few months ago....), two long diff studs, and move the right-hand shock from in front of the axle, to behind the axle (and new upper shock mount), and a notch in the housing for the lock fork. Or if you don't have all that, just swap in a complete e-lock rear axle assembly. This all assuming like-for-like suspension, btw. (Aka leaf front for leaf front). Later 70s (97+ iirc) got coils up front.
Then, for wiring there's a few options. To do it like factory, you would need the elocker control computer (ECU). Then you can use a combo of factory wirings/harnesses and 6-wire trailer wire. Or there is a handful of after market companies making locker controls that include wiring and switches etc.
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